#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int n,a=0,m,b;
    cin>>n>>m>>m;
    for(int i=0; i<n; i++){
        cin>>m>>m>>m>>b;
        a+=b;
    }
    cout<<a;
    return 0;
}