#include <bits/stdc++.h>

#define int long long
#define F first
#define S second
#define pb push_back

using namespace std;

int32_t main ()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);

    int n, s, f;

    cin >> n >> s >> f;

    s--;
    f--;

    vector < pair < int, int >> g[n];

    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            int x;
            cin >> x;
            if (x != -1) g[i].pb({j, x});
        }
    }

    int ans[n];

    for (int i = 0; i < n; i++)
    {
        ans[i] = 1e9;
    }

    priority_queue < pair < int, int>> q;

    q.push({0,s});

    while (!q.empty())
    {
        int v = q.top().S, r = q.top().F;
        r = -r;
        q.pop();

        if (ans[v] < r) continue;

        ans[v]=r;

        for (auto to:g[v])
        {
            if (ans[to.F] > r + to.S)
            {
                ans[to.F] = r + to.S;
                q.push({-(r + to.S), to.F});
            }
        }
    }

    if (ans[f] == 1e9) cout << -1;
    else cout << ans[f];
}