fun main() {
	val (n, sIn, fIn) = readInts()
	val s = sIn - 1; val f = fIn - 1
	val inf = Int.MAX_VALUE / 2
	val matrix = List(n) { readInts().map { if (it == -1) inf else it } }
	val mark = BooleanArray(n) // IntArray заполн. 0, BooleanArray — false
	val dist = IntArray(n) { inf }.also { it[s] = 0 }
	while (true) {
		val v = matrix.indices.filter { !mark[it] }.minByOrNull { dist[it] }
			?.takeIf { dist[it] < inf } ?: break
		mark[v] = true
		for (u in matrix.indices) {
			if (dist[u] > dist[v] + matrix[v][u]) {
				dist[u] = dist[v] + matrix[v][u]
			}
		}
	}
	println(if (dist[f] < inf) dist[f] else -1)
}

fun readLn(): String {
	while (true) {
		val s = readLine()!!.trim()
		if (s.isNotEmpty()) return s
	}
}
fun readStrings() = readLn().split(" ")
fun readInts() = readStrings().map { it.toInt() }