全MLE求助（悲

LIXE_115 @ 2023-06-27 15:43:37

#include<bits/stdc++.h>
using namespace std;
char aa;
int a[101][101];
int n,m;
int f[4][2]={1,0,-1,0,0,1,0,-1};
struct s{
    int x;
    int y;
}no,ne;
bool bfs(){
    no.x=0;
    no.y=0;
    queue<s>q;
    q.push(no);
    while(q.empty()==false){
        //cout<<"-----"<<endl;
        no=q.front();
        q.pop();
        int xx,yy;
        for(int i=0;i<4;i++){
            xx=no.x+f[i][0];
            yy=no.y+f[i][1];
            if(xx>=0&&xx<n&&yy>=0&&yy<m&&a[xx][yy]!=1){
                ne.x=xx;
                ne.y=yy;
                if(xx==n-1&&yy==m-1){
                    return true;
                }
                q.push(ne);
            }
        }
    }
    return false;
}
int main(){
    cin>>n>>m;
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            cin>>aa;
            if(aa=='.'){
                a[i][j]==0;
            }
            if(aa=='#'){
                a[i][j]==1;
            }
        }
    }
    bool ans=bfs();
    if(ans==true){
        cout<<"Yes";
    }
    else{
        cout<<"No";
    }
    return 0;
}

by wangzhanchen @ 2023-06-27 15:45:08

我也跟你一样 你是不是也去看了那个“0分求助”

by wangzhanchen @ 2023-06-27 15:45:57

#include<bits/stdc++.h>
using namespace std;
int n,m,f;
int c[105][105];
char a[105][105];
int dx[5]={0,0,0,-1,1};
int dy[5]={0,-1,1,0,0};
void dfs(int x,int y)
{
    if(x==n&&y==m)
    {
        cout<<"Yes\n";
        f=1;
        return;
    }
    for(int i=1;i<=4;i++)
    {
        int vy,vx;
        vy=y+dy[i];
        vx=x+dx[i];
        if(vx>=1&&vx<=n&&vy>=1&&vy<=m&&a[vx][vy]!='#'&&c[vx][vy]==0)
        {
            c[vx][vy]=1;
            dfs(vx,vy);
            c[vx][vy]=0;
        }
    }
}
int main()
{
    cin>>n>>m;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++)
            cin>>a[i][j];
    dfs(1,1);
    if(f==0)cout<<"No\n";
    return 0;
}

by LIXE_115 @ 2023-06-27 16:28:42

@wangzhanchen 是的（悲，感谢

by coldy_rainy @ 2023-06-27 17:01:23

@LIXE_115

AC代码

#include<bits/stdc++.h>
using namespace std;
char aa;
int a[101][101];
int n,m;
int f[4][2]={1,0,-1,0,0,1,0,-1};
struct s{
    int x;
    int y;
}no,ne;
bool bfs(){
    no.x=0;
    no.y=0;
    queue<s>q;
    q.push(no);
    while(q.empty()==false){
        no=q.front();
        q.pop();
        int xx,yy;
        for(int i=0;i<4;i++){
            xx=no.x+f[i][0];
            yy=no.y+f[i][1];
            if(xx>=0&&xx<n&&yy>=0&&yy<m&&a[xx][yy]!=1){
                ne.x=xx;
                ne.y=yy;
                if(xx==n-1&&yy==m-1){
                    return true;
                }
                a[xx][yy]=1;  //标记当前节点已访问
                q.push(ne);
            }
        }
    }
    return false;
}
int main(){
    cin>>n>>m;
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            cin>>aa;
            if(aa=='.'){
                a[i][j]=0;//用赋值符号
            }
            if(aa=='#'){
                a[i][j]=1;//同
            }
        }
    }
    bool ans=bfs();
    if(ans){
        cout<<"Yes";
    }
    else{
        cout<<"No";
    }
    return 0;
}

by coldy_rainy @ 2023-06-27 17:02:20

@LIXE_115

• 赋值符号是“=”而不是“==”

• 要标记当前节点已访问来保证不会重复经过

by LIXE_115 @ 2023-06-29 21:08:53

@coldy_rainy 才看到，万分感谢！

by coldy_rainy @ 2023-06-30 14:21:37

@LIXE_115

不谢