https://www.luogu.org/problem/P1443
思路：马走日字格，它可以走十六个方向,int dir[8][2]= {2,1,1,2,-2,1,-1,2,2,-1,1,-2,-2,-1,-1,-2}; 将马可以走到的每一步入队列，记录步数
#include <cstdio> #include <iostream> #include <algorithm> #include <cmath> #include <queue> #include <vector> #include <cstring> #include <map> #define mem(a) memset(a,0,sizeof(a)) using namespace std; typedef long long lll; const int maxn = 200005; const lll INF = 0x3f3f3f3f3f; int dir[8][2]= {2,1,1,2,-2,1,-1,2,2,-1,1,-2,-2,-1,-1,-2}; int dir2[4][2]= {0,1,0,-1,1,0,-1,0}; bool flag; int a[1005][1005],b[1005][1005],n,m,sx,sy; string s[1005]; struct node { int x,y; node() {}; node(int xx,int yy):x(xx),y(yy) {}; }; void bfs(int x,int y) { // cout << 1 <<endl; queue<node>q; q.push(node(x,y)); // b[x][y]=1; a[x][y] = 0; while(!q.empty()) { node p = q.front(); q.pop(); for(int i=0; i<8; i++) { int fx = p.x + dir[i][0],fy = p.y + dir[i][1]; if(fx < 1 || fx > n || fy < 1 || fy > m ||a[fx][fy]!=-1||(fx == sx&&fy == sy)) continue; q.push(node(fx,fy)); a[fx][fy] = a[p.x][p.y]+1; // b[fx][fy]=1; } } } int main() { memset(a,-1,sizeof(a)); scanf("%d%d%d%d",&n,&m,&sx,&sy); bfs(sx,sy); for(int i=1; i<=n; i++) { for(int j=1; j<=m; j++) printf("%-5d",a[i][j]); printf(" "); } return 0; }