[Baekjoon-2606] jihoon

BOJ/jihoon/13week/바이러스.cpp

@@ -0,0 +1,50 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int N;
+int con;
+int network[101][101];
+bool visited[101];
+int cnt = 0;
+
+int main() {
+	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
+
+	cin >> N >> con;
+	for (int i = 0; i < con; i++) {
+		int n1, n2;
+		cin >> n1 >> n2;
+		network[n1][n2] = 1;
+		network[n2][n1] = 1;
+	}
+
+	queue<int> q;
+	visited[1] = true;
+	for (int i = 2; i <= N; i++) {
+		if (network[1][i] == 1) {
+			q.push(i);
+			visited[i] = true;
+			cnt++;
+		}
+	}
+
+	while (!q.empty()) {
+		int n = q.front();
+		q.pop();
+
+		for (int i = 1; i <= N; i++) {
+			if (i == n) continue;
+
+			if (network[n][i] == 1 && !visited[i]) {
+				q.push(i);
+				visited[i] = true;
+				cnt++;
+			}
+		}
+	}
+
+	cout << cnt;
+
+	return 0;
+}