#include <fstream>
#include <iostream>
#include <queue>
#include <set>
#include <sstream>
#include <string>
#include <vector>


#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define __PAUSE system("pause");
#define VEC std::vector <
#define QUE std::queue <
#define SET std::set <
#define PAIR std::pair <
#define in std::cin
#define out std::cout

typedef long long ll;
/*
struct set_struct {
  ll marked = 0;
  ll set_vertex;
};  // set data
*/
struct list_struct {
  ll vertex;
  ll len_to_v;
};  // list data

VEC VEC list_struct >> gr;
VEC ll > dist;
ll n, m;

int main() {
  ll start, f;
  in >> n >> start >> f;
  start--;
  f--;
  gr.resize(n);
  dist.resize(n, 1e9);
  for (ll i = 0; i < n; i++) {
    for (ll j = 0; j < n; j++) {
      static ll x;
      in >> x;
      if (x != -1) gr[i].push_back({j, x});
    }
  }
  dist[start] = 0;
  SET PAIR ll, ll>> s;
  s.insert({0, start});
  while (!s.empty()) {
    ll v = s.begin()->second;
    s.erase(s.begin());
    for (auto p : gr[v]) {
      ll u = p.vertex, w = p.len_to_v;
      if (dist[u] > dist[v] + w) {
        s.erase({dist[u], u});
        dist[u] = dist[v] + w;
        s.insert({dist[u], u});
      }
    }
  }
  if (dist[f] == 1e9) {
    out << -1;
    __PAUSE
    return 0;
  }
  out << dist[f] << "\n";
  __PAUSE
}