1009. Product of Polynomials (25)

#include "stdafx.h"
#include <iostream>
#include <map>using namespace std;int main()
{int n1;scanf("%d", &n1);int i, a;double b;map<int, double> m[2];for(i = 1; i <= n1; i++){scanf("%d%lf", &a, &b);m[0][a] = b;}int n2;scanf("%d", &n2);map<int, double> ::reverse_iterator it;int first;double second;for(i = 1; i <= n2; i++){scanf("%d%lf", &a, &b);for(it = m[0].rbegin(); it != m[0].rend(); it++){first = it->first + a;second = it->second * b;m[1][first] += second;}}int count = 0;for(it = m[1].rbegin(); it != m[1].rend(); it++){second = it->second;if(second != 0){count++;}}printf("%d", count);for(it = m[1].rbegin(); it != m[1].rend(); it++){first = it->first;second = it->second;if(second != 0){printf(" %d %.1lf", first, second);}}printf("\n");system("pause");return 0;
}