#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef pair<int,int> P;

vector<vector<int>> a;
int n, m, k;

int dfs(int i, int now){
  if (now > k) return -1;
  if (i == n) return now;
  int ret = -1;
  for (auto e : a[i]) {
    int t = dfs(i+1,now + e);
    if (t == -1) break;
    ret = max(ret,t);
  }
  return ret;
}

int main(){
  
  cin >> n >> m >> k;
  a.resize(n);

  int value = 0;

  rep(i,n) rep(j,m) {
    int c;
    cin >> c;
    a[i].push_back(c);
  }
  int res = dfs(0,0);
  if (res == -1) cout << res << endl;
  else cout << k - res << endl;
  return 0;
}