#pragma region
#pragma GCC target("avx2")
#pragma GCC optimize("03")
#pragma GCC optimize("unroll-loops")
#include <bits/stdc++.h>
using namespace std; typedef long double ld; typedef long long ll;
typedef unsigned long long ull;
#define endl "\n"
#define FOR(i,a,b) for(int i=(a);i<=(b);i++)
#define PII pair<int, int>
#define PLL pair<ll, ll>
#define VPII vector<PII>
#define VPLL vector<PLL>
#define ALL(x) (x).begin(), (x).end()
constexpr int INF=1<<30; constexpr ll LINF=1LL<<60; constexpr ll mod=1e9+7; constexpr int NIL = -1;
template<class T>inline bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T>inline bool chmin(T &a, const T &b) { if (b<a) { a = b; return 1; } return 0; }
#pragma endregion
//-------------------
const int MX = 12;
int a[MX][MX];
int n,m,k;
int ans = INF;

void dfs (int remained, int i) {
    if(i==n-1) {
        FOR(j,0,m-1) {
            if(remained - a[i][j] >= 0) chmin(ans, remained-a[i][j]);
            else break;
        }
        return;
    }

    FOR(j,0,m-1) {
        if(remained-a[i][j] >= 1) {
            dfs(remained-a[i][j], i+1);
        } else {
            break;
        }
    }
}

int main(){
    cin.tie(0); ios::sync_with_stdio(false); //cout << fixed << setprecision(15);
    cin >> n >> m >> k;
    FOR(i,0,n-1) {
        FOR(j,0,m-1) {
            cin >> a[i][j];
        }
    }

    dfs(k, 0);

    if(ans == INF) cout << -1 << endl;
    else cout << ans << endl;
    return 0;
}