我正在尝试将数据作为整数对列表输入,按第一个对值排序对,然后是第二个值,然后输出排序后的对值;
#include <list>
#include <iostream>
#include <algorithm>
//experiment with list sort of pair
using namespace std;
int main (int argc, char* argv[]){
int N,x,y;
list< pair<int,int> >::iterator it;
list< pair<int,int> > a;
cout<<" number of pairs?"<<endl;
cin >> N;
cout<<"enter pairs, with space between 1st and second of pair"<<endl;
for(int i=0;i<N;++i) {
cin >> x >> y;
a.push_back(make_pair(x,y));
}
cout<<"sorted pairs;"<<endl;
sort(a.begin(),a.end()); // Sorts first the x, then the y-coordinate
for (it=a.begin(); it!=a.end(); ++it) {
cout << " " << (*it).first << " " << (*it).second << endl;
}
return 0;
}