[Swift] 백준 2606 바이러스 (Graph Traversal)

 

📌 풀이

💬 Code

let n = Int(readLine()!)!
let m = Int(readLine()!)!

var graph = Array<[Int]>(repeating: [], count: n+1)
var visited = Array<Bool>(repeating: false, count: n+1)

for _ in 0..<m {
    let input = readLine()!.split(separator: " ").map { Int(String($0))! }
    graph[input[0]].append(input[1])
    graph[input[1]].append(input[0])
}

func dfs(start: Int) {
    visited[start] = true
    for i in graph[start] {
        if !visited[i] {
            dfs(start: i)
        }
    }
}

dfs(start: 1)
print(visited.filter{$0}.count - 1)

 

 

2606번: 바이러스