2644. 촌수계산

https://www.acmicpc.net/problem/2644

2644번: 촌수계산

<JAVA>

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.LinkedList;
import java.util.Queue;
import java.util.StringTokenizer;

class Main {
	static int n, m;
	static int num1, num2;
	static int x, y;
	static int depth[] = new int[101];
	static int map[][] = new int[101][101];
	static boolean visit[] = new boolean[101];
	static Queue<Integer> q = new LinkedList<>();

	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st;
		n = Integer.parseInt(br.readLine());
		st = new StringTokenizer(br.readLine(), " ");
		num1 = Integer.parseInt(st.nextToken(" "));
		num2 = Integer.parseInt(st.nextToken(" "));
		m = Integer.parseInt(br.readLine());
		int a, b;
		for (int i = 1; i <= m; i++) {
			st = new StringTokenizer(br.readLine(), " ");
			a = Integer.parseInt(st.nextToken(" "));
			b = Integer.parseInt(st.nextToken(" "));
			map[a][b] = 1;
			map[b][a] = 1;
		}
		visit[num1] = true;
		q.add(num1);
		int temp;
		while (!q.isEmpty()) {
			temp = q.poll();
			for (int i = 1; i <= n; ++i) {
				if (map[temp][i] == 1 && !visit[i]) {
					visit[i] = true;
					depth[i] = depth[temp] + 1;
					q.add(i);
				}
			}
		}
		if (depth[num2] != 0)
			System.out.println(depth[num2]);
		else
			System.out.println("-1");
	}
}

<C++>

#include<iostream>
#include<cstring>
#include<queue>
using namespace std;
int n, m;
int num1, num2;
int x, y;
int depth[101];
int map[101][101];
bool visit[101];
queue <int> q;
int main()
{
	cin.tie(NULL); cout.tie(NULL); ios_base::sync_with_stdio(false);
	cin >> n;
	cin >> num1 >> num2;
	cin >> m;
	int a, b;
	for (int i = 1; i <= m; i++)
	{
		cin >> a >> b;
		map[a][b] = 1;
		map[b][a] = 1;
	}
	visit[num1] = true;
	q.push(num1);
	int temp;
	while (!q.empty())
	{
		temp = q.front(); q.pop();
		for (int i = 1; i <= n; ++i)
		{
			if (map[temp][i] == 1 && !visit[i])
			{
				visit[i] = true;
				depth[i] = depth[temp] + 1;
				q.push(i);
			}
		}
	}
	if (depth[num2] != 0)
		cout << depth[num2] << "\n";
	else
		cout << "-1\n";
	return 0;
}