RE了

Qhy2023 @ 2024-11-19 20:52:48

#include<bits/stdc++.h>
using namespace std;
const int N=405;
struct point{
    int x,y,step;
};
int a[N][N];
int n,m,x,y;
int dx[8]={-2,-1,1,2,2,1,-1,-2},dy[8]={1,2,2,1,-1,-2,-2,-1};

void bfs(){
    queue<point> qu;
    a[x][y]=0;
    qu.push({x,y,0});
    while(!qu.empty()){
        point now=qu.front();
        qu.pop();
        for(int i=0;i<=8;i++){
            int _x,_y;
            _x=now.x+dx[i],_y=now.y+dy[i];
            if(_x>=1&&_x<=n&&_y>=1&&_y<=m&&a[_x][_y]==-1){
                a[_x][_y]=now.step+1;
                qu.push({_x,_y,a[_x][_y]});
            }
        } 
    }
}
int main(){
    cin>>n>>m>>x>>y;
    memset(a,-1,sizeof(a));
    bfs();
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++) cout<<setw(3)<<fixed<<left<<a[i][j];
    cout<<endl;
    }
    return 0;
}

by pengchengen @ 2024-11-28 20:07:16

输出错了 RE应为你bfs的for从0到8了，应该为i<8

#include<bits/stdc++.h>
using namespace std;
const int N=405;
struct point{
    int x,y,step;
};
int a[N][N];
int n,m,x,y;
int dx[8]={-2,-1,1,2,2,1,-1,-2},dy[8]={1,2,2,1,-1,-2,-2,-1};

void bfs(){
    queue<point> qu;
    a[x][y]=0;
    qu.push({x,y,0});
    while(!qu.empty()){
        point now=qu.front();
        qu.pop();
        for(int i=0;i<8;i++){
            int _x,_y;
            _x=now.x+dx[i],_y=now.y+dy[i];
            if(_x>=1&&_x<=n&&_y>=1&&_y<=m&&a[_x][_y]==-1){
                a[_x][_y]=now.step+1;
                qu.push({_x,_y,a[_x][_y]});
            }
        } 
    }
}
int main(){
    cin>>n>>m>>x>>y;
    memset(a,-1,sizeof(a));
    bfs();
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++) cout<<setw(5)<<fixed<<left<<a[i][j];
    cout<<endl;
    }
    return 0;
}