def D(g, n, s):
    visited = [0] * n
    distance = [101] * n
    distance[s - 1] = 0
    for i in range(n):
        min = 102
        u = 0
        for j in range(n):
            if visited[j] == 0 and distance[j] < min:
                min = distance[j]
                u = j
        if distance[u] == 101:
            return -1
        else:
            visited[u] = 1
            for j in range(n):
                if g[u][j] >= 0:
                    if distance[j] > distance[u] + g[u][j]:
                        distance[j] = distance[u] + g[u][j]
    return distance


n, s, f = map(int, input().split())
g = []
for i in range(n):
    l = list(map(int, input().split()))
    g.append(l)
distance = D(g, n, s)
if distance[f - 1] == 101:
    print(-1)
else:
    print(distance[f - 1])