#include <iostream>
#include <vector>
#include <set>
#include <algorithm>
#include <chrono>
#include <cassert>
#include <cstdlib>
#include <math.h>
#include <map>

using namespace std;

int main() {
    int n;
    int k = 34921;
    cin >> n;
    long long int a[k];
    for (int i = 0; i < k; ++i) {
        a[i] = 0;
    }
    for (int i = 0; i < n; ++i) {
        int num, t;
        cin >> num >> t;
        a[num % k] += t;
    }
    int num;
    cin >> num;
    cout << a[num % k];
}