#include <iostream>
#include <fstream>
#include <algorithm>
#include <vector>
#include <string>
#include <math.h>
#include <climits>

#define ll long long
using namespace std;
//freopen("a.in", "r", stdin);
//freopen("a.out", "w", stdout);

int a[2001][2001];
ll used[2001];
int n, s, t, x;

ll xtofs(int v){
    if(v == s)
        return 0;
    ll m = LLONG_MAX;
    ll h;
    for(int i = 0; i < n; i++){
        if(a[v][i] > 0){
            if(used[i] == LLONG_MAX){
                h = xtofs(i);
            }else{
                h = used[i];
            }
            if(h != LLONG_MAX)
                m = min(m, h + a[v][i]);
        }
    }
    used[v] = m;
    return m;
}

int main()
{
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> n >> s >> t;
    fill(used, used + 2001, LLONG_MAX);
    s--;
    t--;
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            cin >> x;
            a[j][i] = x;
        }
    }
    ll q = xtofs(t);
    if(q == LLONG_MAX)
        cout << -1;
    else
        cout << q;
}