C++ | pair

 1 #include <iostream>
 2 #include <string>
 3 #include <vector>
 4 #include <algorithm>
 5 using namespace std;
 6 
 7 int main()
 8 {
 9     typedef pair<int, int> pii;
10     typedef pair<string, pii> psii;
11     vector<psii> grades;
12     grades.push_back(make_pair("a", make_pair(1, 2)));
13     grades.push_back(make_pair("a", make_pair(2, 1)));
14     grades.push_back(make_pair("a", make_pair(1, 3)));
15     grades.push_back(make_pair("b", make_pair(2, 1)));
16     grades.push_back(make_pair("b", make_pair(1, 1)));
17     grades.push_back(make_pair("c", make_pair(1, 1)));
18 
19     sort(grades.begin(), grades.end());
20     vector<psii>::iterator iter, iend = grades.end();
21     for(iter = grades.begin(); iter != iend; ++iter) {
22         cout << iter->first << ‘ ‘ << iter->second.first << ‘ ‘ << iter->second.second << endl;
23     }
24 
25     return 0;
26 }