Standard C++ Library Class Reference

partial_sort should be used.
Complexity
sort performs approximately NlogN, where N equals last - first, comparisons on the average.
Example
//
// sort.cpp
//
#include <vector>
#include <algorithm>
#include <functional>
#include <iostream.h>
struct associate
{
int num;
char chr;
associate(int n, char c) : num(n), chr(c){};
associate() : num(0), chr('\0'){};
};
bool operator<(const associate &x, const associate &y)
{
return x.num < y.num;
}
ostream& operator<<(ostream &s, const associate &x)
{
return s << "<" << x.num << ";" << x.chr << ">";
}
int main ()
{
vector<associate>::iterator i, j, k;
associate arr[20] =
{associate(-4, ' '), associate(16, ' '),
associate(17, ' '), associate(-3, 's'),
associate(14, ' '), associate(-6, ' '),
associate(-1, ' '), associate(-3, 't'),
associate(23, ' '), associate(-3, 'a'),
associate(-2, ' '), associate(-7, ' '),
associate(-3, 'b'), associate(-8, ' '),
associate(11, ' '), associate(-3, 'l'),
associate(15, ' '), associate(-5, ' '),
associate(-3, 'e'), associate(15, ' ')};
// Set up vectors