[배준] 바이러스 (2606)(Kotlin)

원본 문제 : https://www.acmicpc.net/problem/2606

문제 참고 : https://youjourney.tistory.com/132

 

<첫번째>

import java.io.*
import java.util.*

var computerCount = 0
var graph: Array<IntArray> = arrayOf()
val INF: Int = 100000

fun main() = with(BufferedReader(InputStreamReader(System.`in`))) {

    computerCount = readLine().toInt()
    graph = Array( computerCount + 1 ) { IntArray( computerCount + 1) }

    var conn = readLine().toInt()

    for ( i in 1..computerCount ) {
        for ( j in 1..computerCount ) {
            if (i==j) continue
            graph[i][j] = INF
        }
    }

    while ( conn-- > 0 ) {

        val str = readLine().split(" ")
        val start = str[0].toInt()
        val end = str[1].toInt()

        graph[start][end] = Math.min(graph[start][end], 1)
        graph[end][start] = Math.min(graph[end][start], 1)

    }

    floydWarshall()

}

fun floydWarshall() {

    var count = 0

    for ( k in 1..computerCount ) {
        for ( i in 1..computerCount ) {
            for ( j in 1..computerCount ) {
                graph[i][j] = Math.min(graph[i][k] + graph[k][j], graph[i][j])
            }
        }
    }


    for ( i in 1..computerCount ) {
        if ( graph[1][i] >= INF ) graph[1][i] = 0
        if ( graph[1][i] > 0 ) count += 1
    }

    println(count)


}