단계별로 풀어보기 - 반복문 - 4단계
https://www.acmicpc.net/problem/25304
#include <iostream>
using namespace std;
int main()
{
int T,X,sum=0;
cin>>T;
cin>>X;
int Arr[X*2];
for(int i=0;i<X*2;i+=2)
{
cin>>Arr[i]>>Arr[i+1];
sum+=Arr[i]*Arr[i+1];
}
if(sum==T)
{
cout<<"Yes";
}
else
{
cout<<"No";
}
}