Aymen Omer

#include <iostream> using namespace std; int main() { int n, x, y, z, xsum(0), ysum(0), zsum(0); cin >> n; while (n--) { cin >> x >> y >> z; xsum += x; ysum += y; zsum += z; } if (xsum == 0 && ysum == 0 && zsum == 0) { cout << "YES" << endl; } else { cout << "NO" << endl; } return 0; } ما الغرض من while(n--)