codeforce - young physicist

#include<bits/stdC++.h>
using namespace std;
int main()
{
    int n;
    scanf("%d",&n);
    int x=0,e=0,f=0,g=0,a,b,c;
    while(n--)
    {
        scanf("%d %d %d",&a,&b,&c);
        x+=a+b+c;
        e+=a;
        f+=b;
        g+=c;
    }
    if(x==0 && e==0 && f==0 && g==0)
        printf("YES\n");
    else printf("NO\n");
    return 0;
}