![](https://pic.imgdb.cn/item/64303cb20d2dde5777f6c983.png)
AC代码:
#include<iostream>
#include<queue>
#include<cstring>
using namespace std;
const int N = 510;
int ans[N][N],n,m,x,y;
const int dx[8] = { -1,-2,-2,-1,1,2,2,1 };
const int dy[8] = { 2,1,-1,-2,2,1,-1,-2 };
typedef pair<int, int>PII;//开一个可以存两个int的变量,用于存坐标(x,y)
queue<PII> q;
void bfs()
{
//队列非空
while (!q.empty())
{
auto now = q.front();//记录下当前队列首元素
q.pop();//将队列的首元素弹出
int d = ans[now.first][now.second];
for (int i = 0; i < 8; i++)
{
int ax = now.first + dx[i];
int ay = now.second + dy[i];
//如果跨过边界了或者当前位置访问过了,就直接continue不管
if (ax<1 || ax>n || ay<1 || ay>m || ans[ax][ay] != -1)
continue;
ans[ax][ay] = d + 1;//在上一次的距离加上1
q.push({ ax,ay });//继续入队列
}
}
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= m; j++)
{
printf("%-5d", ans[i][j]);
}
puts("");
}
}
int main(void)
{
cin >> n >> m >> x >> y;
memset(ans, -1,sizeof ans);//没有访问就标记为-1
ans[x][y] = 0;//从[x,y]走的,当前格子步数就是0
q.push({ x,y });//将[x,y]坐标加入到队列当中
bfs();
return 0;
}