菊厂笔试3
作者：互联网
马走日
输入一个矩阵，H为开始，T为结束，#为已经放置的棋子，问最少走多少步到达终点
输入样例 H->T
5 13
. . . . . . . . H . . . #
. . . . . . . . # . . . .
. . . . . # . . . . . . .
. # . . . . . . . . . . .
. . . . . . . . . . T # .
输出:
4
5 13
. . . . . H . . . . . . #
. . . . . . . . # . . . .
. . . . . # . . . . . . .
. # . . . . . . . . . . .
. . . . . . . . . . T # .
输出:
3
使用广度优先遍历判别8个方向，走时判断有没有卡马脚问题，和下一步是不是落在已有棋子的位置上。
package com.cgq.thread;
import java.util.LinkedList;
import java.util.Queue;
import java.util.Scanner;
/**
测试样例 H->T
5 13
. . . . . . . . H . . . #
. . . . . . . . # . . . .
. . . . . # . . . . . . .
. # . . . . . . . . . . .
. . . . . . . . . . T # .
输出:
4
5 13
. . . . . H . . . . . . #
. . . . . . . . # . . . .
. . . . . # . . . . . . .
. # . . . . . . . . . . .
. . . . . . . . . . T # .
输出:
3
**/
class Node{
//坐标类
int x;
int y;
public Node(int x, int y) {
this.x = x;
this.y = y;
}
}
public class huawei3 {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
while(scanner.hasNext()){
String[] num = scanner.nextLine().split(" ");
int row = Integer.parseInt(num[0]);
int col = Integer.parseInt(num[1]);
int startx = 0;
int starty = 0;
int endx = 0;
int endy = 0;
int[][] dp = new int[row][col];
boolean[][] visited = new boolean[row][col];
for (int i = 0; i < row; i++) {
String[] input = scanner.nextLine().split(" ");
for (int j = 0; j < col; j++) {
if(input[j].equals(".")){
dp[i][j] = Integer.MAX_VALUE;
}
else if (input[j].equals("#")){
dp[i][j] = -1;
}
else if(input[j].equals("H")){
dp[i][j] = 0;
startx = i;
starty = j;
}
else {
dp[i][j] = Integer.MAX_VALUE;
endx = i;
endy = j;
}
}
}
bfs(startx, starty, endx, endy, dp, visited);
}
}
public static void bfs(int startx, int starty, int endx, int endy, int[][] dp, boolean[][] visited){
Node node = new Node(startx, starty);
visited[startx][starty] = true;
int row = visited.length;
int col = visited[0].length;
Queue<Node> queue = new LinkedList<>();
queue.add(node);
while (!queue.isEmpty()){
Node frontNode = queue.poll();
//方向1 x：-1，y: -2
if(frontNode.x - 1 >= 0 && frontNode.y - 2 >= 0 && !visited[frontNode.x - 1][frontNode.y - 2]){
if(dp[frontNode.x][frontNode.y - 1] != -1 && dp[frontNode.x - 1][frontNode.y - 2] != -1){
visited[frontNode.x - 1][frontNode.y - 2] = true;
queue.add(new Node(frontNode.x - 1, frontNode.y - 2));
dp[frontNode.x - 1][frontNode.y - 2] = Math.min(dp[frontNode.x - 1][frontNode.y - 2], dp[frontNode.x][frontNode.y] + 1);
}
}
//方向2 x：-2，y: -1
if(frontNode.x - 2 >= 0 && frontNode.y - 1 >= 0 && !visited[frontNode.x - 2][frontNode.y - 1]){
if(dp[frontNode.x - 1][frontNode.y] != -1 && dp[frontNode.x - 2][frontNode.y - 1] != -1){
visited[frontNode.x - 2][frontNode.y - 1] = true;
queue.add(new Node(frontNode.x - 2, frontNode.y - 1));
dp[frontNode.x - 2][frontNode.y - 1] = Math.min(dp[frontNode.x - 2][frontNode.y - 1], dp[frontNode.x][frontNode.y] + 1);
}
}
//方向3 x：-2，y: 1
if(frontNode.x - 2 >= 0 && frontNode.y + 1 < col && !visited[frontNode.x - 2][frontNode.y + 1]){
if(dp[frontNode.x - 1][frontNode.y] != -1 && dp[frontNode.x - 2][frontNode.y + 1] != -1){
visited[frontNode.x - 2][frontNode.y + 1] = true;
queue.add(new Node(frontNode.x - 2, frontNode.y + 1));
dp[frontNode.x - 2][frontNode.y + 1] = Math.min(dp[frontNode.x - 2][frontNode.y + 1], dp[frontNode.x][frontNode.y] + 1);
}
}
//方向4 x：-1，y: 2
if(frontNode.x - 1 >= 0 && frontNode.y + 2 < col && !visited[frontNode.x - 1][frontNode.y + 2]){
if(dp[frontNode.x][frontNode.y + 1] != -1 && dp[frontNode.x - 1][frontNode.y + 2] != -1){
visited[frontNode.x - 1][frontNode.y + 2] = true;
queue.add(new Node(frontNode.x - 1, frontNode.y + 2));
dp[frontNode.x - 1][frontNode.y + 2] = Math.min(dp[frontNode.x - 1][frontNode.y + 2], dp[frontNode.x][frontNode.y] + 1);
}
}
//方向5 x：1，y: 2
if(frontNode.x + 1 < row && frontNode.y + 2 < col && !visited[frontNode.x + 1][frontNode.y + 2]){
if(dp[frontNode.x][frontNode.y + 1] != -1 && dp[frontNode.x + 1][frontNode.y + 2] != -1){
visited[frontNode.x + 1][frontNode.y + 2] = true;
queue.add(new Node(frontNode.x + 1, frontNode.y + 2));
dp[frontNode.x + 1][frontNode.y + 2] = Math.min(dp[frontNode.x + 1][frontNode.y + 2], dp[frontNode.x][frontNode.y] + 1);
}
}
//方向6 x：2，y: 1
if(frontNode.x + 2 < row && frontNode.y + 1 < col && !visited[frontNode.x + 2][frontNode.y + 1]){
if(dp[frontNode.x + 1][frontNode.y] != -1 && dp[frontNode.x + 2][frontNode.y + 1] != -1){
visited[frontNode.x + 2][frontNode.y + 1] = true;
queue.add(new Node(frontNode.x + 2, frontNode.y + 1));
dp[frontNode.x + 2][frontNode.y + 1] = Math.min(dp[frontNode.x + 2][frontNode.y + 1], dp[frontNode.x][frontNode.y] + 1);
}
}
//方向7 x：2，y: -1
if(frontNode.x + 2 < row && frontNode.y - 1 >= 0 && !visited[frontNode.x + 2][frontNode.y - 1]){
if(dp[frontNode.x + 1][frontNode.y] != -1 && dp[frontNode.x + 2][frontNode.y - 1] != -1){
visited[frontNode.x + 2][frontNode.y - 1] = true;
queue.add(new Node(frontNode.x + 2, frontNode.y - 1));
dp[frontNode.x + 2][frontNode.y - 1] = Math.min(dp[frontNode.x + 2][frontNode.y - 1], dp[frontNode.x][frontNode.y] + 1);
}
}
//方向8 x：1，y: -2
if(frontNode.x + 1 < row && frontNode.y - 2 >= 0 && !visited[frontNode.x + 1][frontNode.y - 2]){
if(dp[frontNode.x][frontNode.y - 1] != -1 && dp[frontNode.x + 1][frontNode.y - 2] != -1){
visited[frontNode.x + 1][frontNode.y - 2] = true;
queue.add(new Node(frontNode.x + 1, frontNode.y - 2));
dp[frontNode.x + 1][frontNode.y - 2] = Math.min(dp[frontNode.x + 1][frontNode.y - 2], dp[frontNode.x][frontNode.y] + 1);
}
}
}
if(dp[endx][endy] == Integer.MAX_VALUE){
System.out.println(-1);
}
else {
System.out.println(dp[endx][endy]);
}
}
}
标签：int,笔试,frontNode,菊厂,&&,new,visited,dp 来源： https://blog.csdn.net/qq_33477072/article/details/119136792