============================ModuleX=======================================
|                                                                         |
|  The program examples' source codes have been arranged in the same      |
|  order that appeared in the Tutorial. This is unedited and unverified   |
|  compilation. Published as is basis for educational, reacretional and   |
|  brain teaser purposes. All trademarks, copyrights and IPs, wherever    |
|  exist, are the sole property of their respective owner and/or          |
|  holder. Any damage or loss by using the materials presented in this    |
|  tutorial is USER responsibility. Part or full distribution,            |
|  reproduction and modification is granted to any body.                  |
|     Copyright 2003-2005 © Tenouk, Inc. All rights reserved.		  |
|          Distributed through http://www.tenouk.com			        |
|        		                                                        |
|									                    |
===========================================================================
Originally programs compiled using Borland C++. Examples compiled using
VC++/VC++ .Net and gcc or g++ are given at the end of every Module.
For example if you want to compile C++ codes using VC++/VC++ .Net, change
the header file accordingly.  Just need some modification for the header
files...:

-------------------------------------------------
#include <iostream.h>
//for system()
#include <stdlib.h>

...
{
C++ codes...
}
-------------------------------------------------
should be changed to:
-------------------------------------------------
#include <iostream>
//use C++ wrapper to call C functions from C++ programs...
#include <cstdlib>
using namespace std;

...
{
C++ codes...
}
-------------------------------------------------
In VC++/VC++ .Net the iostream.h (header with .h) is not valid anymore.
It should be C++ header, <iostream> so that it comply to the standard.
In older Borland C++ compiler this still works, but not proper any more...
and for standard C/C++ the portability should be no problem or better
you read Module23 at http://www.tenouk.com/Module23.html to get
the big picture...For C codes, they still C codes :o)
=========================================================================
=========================================================================


//Using functions isdigit(), isalpha(), isalnum(), and isxdigit()
//but using C++ :o), cout…
#include <iostream.h>
#include <stdlib.h>
#include <ctype.h>

int main()
{
cout<<"Using functions isdigit(), isalpha(),"<<endl;
cout<<"isalnum(), and isxdigit()"<<endl;
cout<<"-------------------------------------"<<endl;

cout<<"\nAccording to isdigit():"<<endl;
isdigit('8') ? cout<<"8 is a digit\n" : cout<<"8 is not a digit\n";
isdigit('#') ? cout<<"# is a digit\n" : cout<<"# is not a digit\n";

cout<<"\nAccording to isalpha():"<<endl;
isalpha('A') ? cout<<"A is a letter\n" : cout<<"A is not a letter\n";
isalpha('b') ? cout<<"b is a letter\n" : cout<<"b is not a letter\n";
isalpha('&') ? cout<<"& is a letter\n" : cout<<"& is not a letter\n";
isalpha('4') ? cout<<"4 is a letter\n" : cout<<"4 is not a letter\n";

cout<<"\nAccording to isalnum():"<<endl;
isalnum('A') ? cout<<"A is a digit or a letter\n" : cout<<"A is not a digit or a letter\n";
isalnum('8') ? cout<<"8 is a digit or a letter\n" : cout<<"8 is not a digit or a letter\n";
isalnum('#') ? cout<<"# is a digit or a letter\n" : cout<<"# is not a digit or a letter\n";

cout<<"\nAccording to isxdigit():"<<endl;
isxdigit('F') ? cout<<"F is a hexadecimal\n" : cout<<"F is not a hexadecimal\n";
isxdigit('J') ? cout<<"J is a hexadecimal\n" : cout<<"J is not a hexadecimal\n";
isxdigit('7') ? cout<<"7 is a hexadecimal\n" : cout<<"7 is not a hexadecimal\n";
isxdigit('$') ? cout<<"$ is a hexadecimal\n" : cout<<"$ is not a hexadecimal\n";
isxdigit('f') ? cout<<"f is a hexadecimal\n" : cout<<"f is not a hexadecimal\n";

system("pause");
return 0;
}

------------------------------------------VC++/VC++ .Net----------------------------------------------------

//Using functions isdigit(), isalpha(), isalnum(), and isxdigit()
//but using C++, VC++/VC++ .Net
#include <iostream>
#include <cstdlib>
using namespace std;

int main()
{
cout<<"Using functions isdigit(), isalpha(),"<<endl;
cout<<"isalnum(), and isxdigit()"<<endl;
cout<<"-------------------------------------"<<endl;

cout<<"\nAccording to isdigit():"<<endl;
isdigit('8') ? cout<<"8 is a digit\n" : cout<<"8 is not a digit\n";
isdigit('#') ? cout<<"# is a digit\n" : cout<<"# is not a digit\n";

cout<<"\nAccording to isalpha():"<<endl;
isalpha('A') ? cout<<"A is a letter\n" : cout<<"A is not a letter\n";
isalpha('b') ? cout<<"b is a letter\n" : cout<<"b is not a letter\n";
isalpha('&') ? cout<<"& is a letter\n" : cout<<"& is not a letter\n";
isalpha('4') ? cout<<"4 is a letter\n" : cout<<"4 is not a letter\n";

cout<<"\nAccording to isalnum():"<<endl;
isalnum('A') ? cout<<"A is a digit or a letter\n" : cout<<"A is not a digit or a letter\n";
isalnum('8') ? cout<<"8 is a digit or a letter\n" : cout<<"8 is not a digit or a letter\n";
isalnum('#') ? cout<<"# is a digit or a letter\n" : cout<<"# is not a digit or a letter\n";

cout<<"\nAccording to isxdigit():"<<endl;
isxdigit('F') ? cout<<"F is a hexadecimal\n" : cout<<"F is not a hexadecimal\n";
isxdigit('J') ? cout<<"J is a hexadecimal\n" : cout<<"J is not a hexadecimal\n";
isxdigit('7') ? cout<<"7 is a hexadecimal\n" : cout<<"7 is not a hexadecimal\n";
isxdigit('$') ? cout<<"$ is a hexadecimal\n" : cout<<"$ is not a hexadecimal\n";
isxdigit('f') ? cout<<"f is a hexadecimal\n" : cout<<"f is not a hexadecimal\n";

system("pause");
return 0;
}

------------------------------------------VC++/VC++ .Net----------------------------------------------------

//Using functions islower(), isupper(), tolower(), toupper()
//For VC++/VC++ .Net use the following header files...
//#include <iostream>
//#include <cstdlib>
//using namespace std;

#include <iostream.h>
#include <stdlib.h>
#include <ctype.h>

int main()
{

cout<<"Using functions islower(), isupper(),"<<endl;
cout<<"tolower(), toupper()"<<endl;
cout<<"-------------------------------------"<<endl;

cout<<"\nAccording to islower():"<<endl;
islower('p') ? cout<<"p is a lowercase letter\n" : cout<<"p is not a lowercase letter\n";
islower('P') ? cout<<"P is a lowercase letter\n" : cout<<"P is not a lowercase letter\n";
islower('5') ? cout<<"5 is a lowercase letter\n" : cout<<"5 is not a lowercase letter\n";
islower('!') ? cout<<"! is a lowercase letter\n" : cout<<"! is not a lowercase letter\n";

cout<<"\nAccording to isupper():"<<endl;
isupper('D') ? cout<<"D is a uppercase letter\n" : cout<<"D is not a uppercase letter\n";
isupper('d') ? cout<<"d is a uppercase letter\n" : cout<<"d is not a uppercase letter\n";
isupper('8') ? cout<<"8 is a uppercase letter\n" : cout<<"8 is not a uppercase letter\n";
isupper('$') ? cout<<"$ is a uppercase letter\n" : cout<<"$ is not a uppercase letter\n";

cout<<"\nConversion...."<<endl;
cout<<"u converted to uppercase is "<<(char)toupper('u')<<endl;
cout<<"7 converted to uppercase is "<<(char)toupper('7')<<endl;
cout<<"$ converted to uppercase is "<<(char)toupper('$')<<endl;
cout<<"L converted to lowercase is "<<(char)tolower('L')<<endl;
system("pause");
return 0;
}

--------------------------------------------------------------------------------------------------------

//using functions isspace(), iscntrl(), ispunct(),
//isprint(), isgraph()
#include <iostream.h>
#include <stdlib.h>
#include <ctype.h>

int main()
{
cout<<"using functions isspace(), iscntrl(),"<<endl;
cout<<"ispunct(), isprint(), isgraph()"<<endl;
cout<<"-------------------------------------"<<endl;

cout<<"According to isspace(): "<<endl;
isspace('\n') ? cout<<"Newline is a whitespace character\n" :
		cout<<"Newline is not a whitespace character\n";
isspace('\t') ? cout<<"Horizontal tab is a whitespace character\n" :
		cout<<"Horizontal tab is not a whitespace character\n";
isspace('%') ? cout<<"% is a whitespace character\n" :
		cout<<"% is not a whitespace character\n";

cout<<"\nAccording to iscntrl(): "<<endl;
iscntrl('\n') ? cout<<"Newline is a control character\n" :
		cout<<"Newline is not a control character\n";
iscntrl('$') ? cout<<"$ is a control character\n" :
		cout<<"$ is not a control character\n";

cout<<"\nAccording to ispunct(): "<<endl;
ispunct('y') ? cout<<"y is a punctuation character\n" :
		cout<<"y is not a punctuation character\n";
ispunct('\'') ? cout<<"\' is a punctuation character\n" :
		cout<<"\' is not a punctuation character\n";
ispunct('"') ? cout<<"\" is a punctuation character\n" :
		cout<<"\" is not a punctuation character\n";

cout<<"\nAccording to isprint(): "<<endl;
isprint('$') ? cout<<"$ is a printing character\n" :
		cout<<"$ is not a printing character\n";
isprint('\a') ? cout<<"Alert is a printing character\n" :
		cout<<"Alert is not a printing character\n";

cout<<"\nAccording to isgraph(): "<<endl;
isgraph('Q') ? cout<<"Q is a printing character other than a space\n" :
		cout<<"Q is not a printing character other than a space\n";
isgraph(' ') ? cout<<"Space is a printing character other than a space\n":
		cout<<"Space is not a printing character other than a space\n";
system("pause");
return 0;
}

--------------------------------------------------------------------------------------------------------

//using atof() - converting string to double
#include <stdio.h>
#include <stdlib.h>

int main()
{
		double  dou;
		dou = atof("95.0");

		printf("Using atof() - converting string to double\n");
		printf("------------------------------------------\n\n");

		printf("The string \"95.0\" when converted to double is %.3f\n", dou);
		printf("The converted value, %.3f divided by 2 is %.3f\n", dou, dou / 2.0);

		system("pause");
		return 0;
}

--------------------------------------------------------------------------------------------------------

//using atoi() - converting string to integer
#include <stdio.h>
#include <stdlib.h>

int main()
{
	int  i;
	i = atoi("1234");

	printf("Using atoi() - converting string to integer\n");
	printf("-------------------------------------------\n\n");

	printf("The string \"1234\" converted to int is %d\n", i);
	printf("The converted value %d minus 123 is %d\n", i, i - 123);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using atol() - converting string to long
#include <stdio.h>
#include <stdlib.h>

int main()
{
	long newlong;
	newlong = atol("123456");

	printf("Using atol() - converting string to long\n");
	printf("----------------------------------------\n\n");

	printf("The string \"123456\" converted to long int is %ld\n", newlong);
	printf("The converted value, %ld divided by 2 is %ld\n", newlong, newlong / 2);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//using strtod() - string to double
#include <stdio.h>
#include <stdlib.h>

int main()
{
	double p;
	char *thestring = "41.2% sample string";
	char *thestringPtr;

	p = strtod(thestring, &thestringPtr);

	printf("Using strtod() - converting string to double...\n");
	printf("-------------------------------------------\n\n");

	printf("The string \"%s\" is converted to the\n", thestring);
	printf("double value %.2f and the string \"%s\" \n", p, thestringPtr);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strtol()-converting string to
//long with 3 arguments
#include <stdio.h>
#include <stdlib.h>

int main()
{
	long x;
	char  *thestring = "-1234567abc", *remainderPtr;

	x = strtol(thestring, &remainderPtr, 0);

	printf("Using strtol() - converting string to long,\n");
	printf("              3 arguments...\n");
	printf("-------------------------------------------\n\n");

	printf("The original string is \"%s\"\n", thestring);
	printf("The converted value is %ld\n", x);
	printf("The remainder of the original string is \"%s\"\n", remainderPtr);
	printf("The converted value, %ld plus 567 is %ld\n", x, x + 567);
	system("pause");
	return  0;
}

--------------------------------------------------------------------------------------------------------

//Using strtoul() - converting string to
//unsigned long with 3 arguments
#include <stdio.h>
#include <stdlib.h>

int main()
{
	unsigned long x;
	char *thestring = "1234567def", *remainderPtr;

	x = strtoul(thestring, &remainderPtr, 0);

	printf("Using strtoul() - converting string to\n");
	printf("   unsigned long, 3 arguments\n");
	printf("---------------------------------------\n\n");

	printf("The original string is \"%s\"\n", thestring);
	printf("The converted value is %lu\n", x);
	printf("The remainder of the original string is \"%s\"\n", remainderPtr);
	printf("The converted value, %lu minus 567 is %lu\n", x, x - 567);
	system("pause");
	return  0;
}

--------------------------------------------------------------------------------------------------------

//Using gets() and putchar()
#include <stdio.h>
#include <stdlib.h>

//function prototype...
void  reverse(char *);

int main()
{
	//an array for storing the string...
	char sentence[80];

	printf("Using gets() and putchar()\n");
	printf("--------------------------\n");

	//prompt for user input...
	printf("Enter a line of text:\n");
	gets(sentence);

	printf("\nThe line printed backward is:\n");
	//reverse() function call...
	reverse(sentence);
	printf("\n");
	system("pause");
	return 0;
}

void reverse(char *s)
{
	//test if nothing entered...
	if(s[0] == '\0')
		return;
	//if something entered...
	else
	{
		reverse(&s[1]);
		putchar(s[0]);
	}
} 	

--------------------------------------------------------------------------------------------------------

//using getchar() and puts()
#include <stdio.h>
#include <stdlib.h>

int main()
{
	char  c, sentence[80];
	int i = 0;

	printf("Using getchar() and puts()\n");
	printf("--------------------------\n");
	puts("Enter a line of text: ");

	//while iteration/loop…
	while (( c = getchar()) != '\n')
		sentence[i++] = c;
		//insert NULL at the end of string
		sentence[i] = '\0';
		puts("\nThe line of text entered was: ");
		puts(sentence);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using sprintf()
#include <stdio.h>
#include <stdlib.h>

int main()
{
	char s[80];
	int  x;
	float  y;

	printf("Using sprint()\n");
	printf("--------------\n");
	printf("Enter an integer and a float, separated by space: \n");
	scanf("%d%f", &x, &y);
	sprintf(s, "Integer:%6d\nFloat:%8.2f", x, y);
	printf("\n%s\n%s\n",
   		"The formatted output stored in array s is:  ", s);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using sscanf()
#include <stdio.h>
#include <stdlib.h>
  
int main()
{
	char s[] = "31298    87.375";
	int  x;
	float  y;

	printf("Using sscanf()\n");
	printf("--------------\n");
	sscanf(s, "%d%f", &x, &y);
	printf("array, s[] = 31298    87.375\n");
	printf("\n%s\n%s%6d\n%s%8.3f\n",
    		"The values stored in character array s are: ",
    		"Integer: ",  x,  "Float: ", y);
	system("pause");
	return   0;
}

--------------------------------------------------------------------------------------------------------

//Using strcpy() and strncpy()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char  x[] = "Yo! Happy Birthday to me";
	char  y[25],  z[15];

	printf("Using strcpy() and strncpy()\n");
	printf("----------------------------\n");

	printf("The string in array x is: %s\n", x);
	printf("The string in array y is: %s\n", strcpy(y, x));

	strncpy(z, x, 14);
	z[14] = '\0';
	
	printf("Only 14 characters ....\n", z);
	printf("The string in array z is: %s\n", z);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strcat() and strncat()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char s1[20] = "Happy ";
	char s2[] = "New Year ";
	char s3[40] = " ";

	printf("Using strcat() and strncat()\n");
	printf("--------------------------\n");

	printf("s1 = %s\ns2 = %s\n", s1, s2);
	printf("\nstrcat (s1, s2) = %s\n", strcat(s1, s2));
	printf("strncat (s1, s2, 6) = %s\n", strncat(s3, s1, 6));
	printf("strcat(s3, s1) = %s\n", strcat(s3, s1));
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strcmp() and strncmp()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char * s1 = "Happy New Year";
	char  *s2 = "Happy New Year";
	char  *s3 = "Happy Birthday";

	printf("Using strcmp() and strncmp()\n");
	printf("----------------------------\n");

	printf("s1 = %s\n", s1);
	printf("s2 = %s\n", s2); 
	printf("s3 = %s\n", s3);
	printf("\nstrcmp(s1, s2) = %2d\n", strcmp(s1, s2));
	printf("strcmp(s1, s3) = %2d\n", strcmp(s1, s3));
	printf("strcmp(s3, s1) = %2d\n", strcmp(s3, s2));
	
	printf("\nstrncmp(s1, s3, 6) = %2d\n", strncmp(s1, s3, 6));
	printf("strncmp(s1, s3, 7) = %2d\n", strncmp(s1, s3, 7));
	printf("strncmp(s1, s1, 7) = %2d\n", strncmp(s1, s3, 7));
	system("pause");
	return  0;
} 

--------------------------------------------------------------------------------------------------------

//Using strchr()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char *string = "This is a test statement, testing! ";
	char character1 = ‘e’, character2 = ‘z’;

	printf("		Using strchr()\n");
	printf("		--------------\n");

	if (strchr(string, character1) != NULL)
		printf("\’%c\’ was found in \"%s\".\n", character1, string);
	else
		printf("\’%c\’ was not found in \"%s\".\n", character1, string);

	if(strchr(string, character2) != NULL)
		printf("\’%c\’ was found in \"%s\".\n", character2, string);
	else
		printf("\’%c\’ was not found in \"%s\".\n", character2, string);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strcspn()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char *string1 = "The value is 3.14159";
	char *string2 = "1234567890";

	printf("	Using strcspn()\n");
	printf("	---------------\n");
	printf("string1 = %s\n", string1);
	printf("string2 = %s\n", string2);
	printf("\nThe length of the initial segment of string1\n");
	printf("not containing characters from string2 = %u", strcspn(string1, string2));
	printf("\n");
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strpbrk()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char *string1 = "This is a test statement";
	char *string2 = "search";

	printf("	Using strpbrk()\n");
	printf("	---------------\n");

		printf("In \"%s\" string, a character \’%c\’\n", string2, *strpbrk(string1, string2));
	printf("is the first character to appear in\n\"%s\"\n", string1);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strchr()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char *string1 = "A zoo has many animals including birds";
	int c = ‘m’;

	printf("	Using strchr()\n");
	printf(“	---------------\n");
   	printf("string1 = %s\n", string1);

	printf("\nThe remainder of string1 beginning with the\n");
	printf("last occurrence of character \’%c\’", c);
	printf("\nis:  %s\n", strrchr(string1, c));
	system("pause");
	return 0;
} 

--------------------------------------------------------------------------------------------------------

//Using strspn()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char *string1 = "The initial value is 3.14159";
	char *string2 = "aehilsTuv";


	printf("	Using strspn()\n");
	printf("	---------------\n");

	printf("string1 = %s\n", string1);
   	printf("string2 = %s\n", string2);
	printf("\nThe length of the initial segment of string1\n");
	printf("containing only characters from string2 is = %u\n", strspn(string1, string2));
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strstr()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char *string1 = "abcdefgabcdefgabcdefg";
	char *string2 = "defg";

	printf("	Using strstr()\n");
	printf("	---------------\n");

	printf("string1 = %s\n", string1);
	printf("string2 = %s\n", string2);
	printf("\nThe remainder of string1 beginning with the");
	printf("\nfirst occurrence of string2 is: %s\n", strstr(string1, string2));
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using strtok()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char string[] = "Is this sentence has 6 tokens?";
	char *tokenPtr;

	printf("	Using strtok()\n");
	printf("	--------------\n");

	printf("The string to be tokenized is:\n%s\n", string);
	printf("\nThe tokens are: \n\n");
	
	tokenPtr = strtok(string, " ");
	while (tokenPtr != NULL)
		{
			printf("%s\n", tokenPtr);
			tokenPtr  =  strtok(NULL, " ");
		}
	system("pause");
	return   0;
}

--------------------------------------------------------------------------------------------------------

//Using memcpy()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char s1[20], s2[] = "Copying this string into s1";

	memcpy(s1, s2, 17);

	printf("	Using memcpy()\n");
	printf("	--------------\n");

	printf("s1[20] = ?\n", s1);
	printf("s2[] = %s\n", s2);

	printf("\nAfter s2 is copied into s1 with memcpy(),\n");
	printf("using memcpy(s1, s2, 17)\n");
	printf("\ns1 contains \"%s\"\n", s1);
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using memmove()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char x[] = "My home is home sweet home";

	printf("	Using memmove()\n");
	printf("	--------------\n");
	printf("The string in array x before memmove() is: \n%s", x);
	printf("\nThe string in array x after memmove() using \n");
	printf("memmove(x, &x[7], 12) is:\n %s\n", memmove(x, &x[7], 12));
	system("pause");
	return  0;
}

--------------------------------------------------------------------------------------------------------

//Using memcmp()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char s1[] = "ABCDEFGHIJK", s2[] = "ABCDXYZPQR";

	printf("Using memcmp()\n");
	printf("--------------\n");

	printf("s1 = %s\n", s1);
	printf("s2 = %s\n", s2);
	printf("\nmemcmp(s1, s2, 4) = %2d\n", memcmp(s1, s2, 4));
	printf("memcmp(s1, s2, 7) = %2d\n", memcmp(s1, s2, 7));
	printf("memcmp(s2, s1, 7) = %2d\n", memcmp(s2, s1, 7));
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using memchr()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char *s = "This is a test string";
	char p = 'e';
	
	printf("Using memchr()\n");
	printf("--------------\n");

	printf("char p = \'e\'\n");
	printf("s = %s\n", s);

	printf("\nThe remainder of string s, after character \'%c\'", p);
	printf("\nis found, using memchr(s, p, 15)");
	printf("\nis \"%s\"\n", memchr(s, p, 15));
	system("pause");
	return 0;
}

--------------------------------------------------------------------------------------------------------

//Using memset()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	char string[40] = "AAAAAAAABBBBBBBBBCCCCCCCCCC";

	printf("Using memset()\n");
	printf("--------------\n");

	printf("string = %s\n", string);
	printf("string after memset(string, 'b', 15) =\n%s\n",
			memset(string, 'b', 15));
	system("pause");
	return  0;
}

--------------------------------------------------------------------------------------------------------

//Using strerror()
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main()
{
	printf("strerror() - string errors\n");
	printf("--------------------------\n");
	printf("strerror(1)->%s", strerror(1));
	printf("strerror(2)->%s", strerror(2));
	printf("strerror(3)->%s", strerror(3));
	printf("strerror(4)->%s", strerror(4));
	printf("strerror(5)->%s", strerror(5));
	printf("strerror(6)->%s", strerror(6));
	printf("strerror(7)->%s", strerror(7));
	printf("strerror(8)->%s", strerror(8));
	printf("strerror(9)->%s", strerror(9));
	printf("strerror(9)->%s", strerror(9));
	printf("strerror(10)->%s", strerror(10));
	system("pause");
	return 0;
}

----------------------------VC++/VC++ .net---------------------------------------------------------------

//Using strchr()
#include <cstdio>
#include <cstring>
using namespace std;

int main()
{
	char *string1 = "A zoo has many animals including birds";
	int c = 'm';

	printf("	Using strchr()\n");
	printf("	---------------\n");
   	printf("string1 = %s\n", string1);

	printf("\nThe remainder of string1 beginning with the\n");
	printf("last occurrence of character \'%c\'", c);
	printf("\nis:  %s\n", strrchr(string1, c));
	return 0;
} 

------------------------------------G++--------------------------------------------------------------------

//*****ctystring.cpp******
//Using sprintf()
#include <cstdio>
using namespace std;

int main()
{
  char s[80];
  int  x;
  float  y;

  printf("Using sprint()\n");
  printf("--------------\n");
  printf("Enter an integer and a float, separated by space: \n");
  scanf("%d%f", &x, &y);
  sprintf(s, "Integer:%6d\nFloat:%8.2f", x, y);
  printf("\n%s\n%s\n",
        "The formatted output stored in array s is:  ", s);
  return 0;
}

-------------------------------------GCc-------------------------------------------------------------------

/****ctstring2.c, using memcpy()*/
#include <stdio.h>
#include <string.h>

int main()
{
  char s1[20], s2[] = "Copying this string into s1";
  memcpy(s1, s2, 17);
  printf("      Using memcpy()\n");
  printf("      --------------\n");
  printf("s1[20] = ?\n", s1);
  printf("s2[] = %s\n", s2);
  printf("\nAfter s2 is copied into s1 with memcpy(),\n");
  printf("using memcpy(s1, s2, 17)\n");
  printf("\ns1 contains \"%s\"\n", s1);
  return 0;
}

-------------------------------------Gcc-------------------------------------------------------------------

/*******************cstr.c**************************/
/*Using functions isdigit(), isalpha(), isalnum(), and isxdigit()*/
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>

int main()
{
printf("Using functions isdigit(), isalpha(),\n");
printf("isalnum(), and isxdigit()\n");
printf("-------------------------------------\n");

printf("\nAccording to isdigit():\n");
isdigit('7') ? printf("7 is a digit\n") : printf("7 is not a digit\n");
isdigit('$') ? printf("$ is a digit\n") : printf("$ is not a digit\n");

printf("\nAccording to isalpha():\n");
isalpha('B') ? printf("B is a letter\n") : printf("B is not a letter\n");
isalpha('b') ? printf("b is a letter\n") : printf("b is not a letter\n");
isalpha('&') ? printf("& is a letter\n") : printf("& is not a letter\n");
isalpha('4') ? printf("4 is a letter\n") : printf("4 is not a letter\n");

printf("\nAccording to isalnum():\n");
isalnum('A') ? printf("A is a digit or a letter\n") : printf("A is not a digit or a letter\n");
isalnum('8') ? printf("8 is a digit or a letter\n") : printf("8 is not a digit or a letter\n");
isalnum('#') ? printf("# is a digit or a letter\n") : printf("# is not a digit or a letter\n");

printf("\nAccording to isxdigit():\n");
isxdigit('F') ? printf("F is a hexadecimal\n") : printf("F is not a hexadecimal\n");
isxdigit('J') ? printf("J is a hexadecimal\n") : printf("J is not a hexadecimal\n");
isxdigit('7') ? printf("7 is a hexadecimal\n") : printf("7 is not a hexadecimal\n");
isxdigit('$') ? printf("$ is a hexadecimal\n") : printf("$ is not a hexadecimal\n");
isxdigit('f') ? printf("f is a hexadecimal\n") : printf("f is not a hexadecimal\n");

return 0;
}

===========================================================================================================