[백준] 6601 Knight Moves - Graph Theory / Java

• 문제 링크

6601번: Knight Moves

 

• 풀이 코드

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayDeque;
import java.util.Queue;
import java.util.StringTokenizer;

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        StringBuilder sb = new StringBuilder();

        int[][] dir = {{1, 2}, {1, -2}, {-1, 2}, {-1, -2}, {2, 1}, {2, -1}, {-2, 1}, {-2, -1}};
        String s;
        while ((s = br.readLine()) != null) {
            StringTokenizer st = new StringTokenizer(s);
            String a = st.nextToken(), b = st.nextToken();
            Pair src = new Pair(a.charAt(0) - 'a', a.charAt(1) - '1'), tgt = new Pair(b.charAt(0) - 'a', b.charAt(1) - '1');

            Queue<Pair> q = new ArrayDeque<>();
            int[][] mat = new int[8][8];

            q.offer(src);
            while (!q.isEmpty()) {
                Pair cur = q.poll();
                if (cur.y == tgt.y && cur.x == tgt.x) break;

                for (int[] d : dir) {
                    int ny = cur.y + d[0], nx = cur.x + d[1];
                    if (ny < 0 || ny >= 8 || nx < 0 || nx >= 8 || mat[ny][nx] != 0) continue;

                    q.offer(new Pair(ny, nx));
                    mat[ny][nx] = mat[cur.y][cur.x] + 1;
                }
            }

            sb.append("To get from ").append(a).append(" to ").append(b).append(" takes ").append(mat[tgt.y][tgt.x]).append(" knight moves.\n");
        }

        bw.write(sb.toString());
        bw.flush();
    }

    private static class Pair {
        int y, x;

        Pair(int y, int x) {
            this.y = y;
            this.x = x;
        }
    }

}