C++ STL multimap, key_compare program example
Compiler: Visual C++ Express Edition 2005
Compiled on Platform: Windows XP Pro SP2
Header file: Standard
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Project -> your_project_name Properties -> Configuration Properties -> C/C++ -> Advanced -> Compiled As: Compiled as C++ Code (/TP)
Other info:
To do: Using the C++ key_compare which is a type that provides a function object that can compare two sort keys to determine the relative order of two elements in the multimap in C++ programming
To show: How to use the C++ multimap, key_compare key_compare which is a type that provides a function object that can compare two sort keys to determine the relative order of two elements in the multimap in C++ programming
// C++ STL multimap, key_compare
#include <map>
#include <iostream>
using namespace std;
int main(void)
{
multimap <int, int, less<int> > m1;
multimap <int, int, less<int> >::key_compare kcomp1 = m1.key_comp();
bool result1 = kcomp1(2, 3);
if(result1 == true)
{
cout<<"kcomp1(2,3) returns value of true, where kcomp1 is the function object of m1."<<endl;
}
else
{
cout<<"kcomp1(2,3) returns value of false where kcomp1 is the function object of m1."<<endl;
}
multimap <int, int, greater<int> > m2;
multimap <int, int, greater<int> >::key_compare kcomp2 = m2.key_comp();
bool result2 = kcomp2(2, 3);
if(result2 == true)
{
cout<<"kcomp2(2,3) returns value of true, where kcomp2 is the function object of m2."<<endl;
}
else
{
cout<<"kcomp2(2,3) returns value of false, where kcomp2 is the function object of m2."<<endl;
}
return 0;
}
Output examples:
kcomp1(2,3) returns value of true, where kcomp1 is the function object of m1.
kcomp2(2,3) returns value of false, where kcomp2 is the function object of m2.
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