#include <bits/stdc++.h>
#define int long long
using namespace std;
const int INF = 1LL << 60;
const int MOD = (int) 1e9 + 7;

signed main(){
    int n, m, k;
    cin >> n >> m >> k;
    vector<vector<int>> v(n, vector<int>());
    int ans = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            int x;
            cin >> x;
            if (j == 0)
                ans += x;
            v[i].push_back(x);
        }
    }
    if (ans > k) {
        cout << -1 << "\n";
        return 0;
    }
    for (int i = n - 1; i >= 0; i--) {
        for (int j = m - 1; j > 0; j--) {
            if (ans + v[i][j] <= k)
                ans += v[i][j];
        }
    }
    cout << k - ans << "\n";
}