《图》DFS和BFS(C++)

前言:

之前实现过Java版的dfs,bfs:dfs,bfs求最短路径, java实现,现在用c++再实现一次。

代码:

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<queue>
#include<stack>
#include<map>
#include<math.h>
#include<set>
#include<list>
#include<string>
#include<cstring>
#define maxn 50
#define INF 0x7fffffff

using namespace std;

int n,m;
char c[maxn][maxn];
bool vis[maxn][maxn];
int dx[4]={-1,0,1,0};
int dy[4]={0,-1,0,1};

struct coordinate{
    int x,y,d;
};

bool isOk(int x,int y,int n,char c[][maxn])
{
    if(x>=0&&x<n&&y>=0&&y<n&&!vis[x][y]&&c[x][y]!='#')
        return true;
    return false;
};

int counter=INF;
int dfs(int x,int y,int d,int n)
{
    vis[x][y]=true;
    for(int i=0;i<4;i++)
    {
        int xx=x+dx[i];
        int yy=y+dy[i];
        //cout<<"xx,yy"<<xx<<" "<<yy<<endl;
        if(isOk(xx,yy,n,c))
        {
            vis[xx][yy]=true;
            int dd=d+1;
            if(c[xx][yy]=='0')
            {
                //cout<<"dd:"<<dd<<endl;
                if(dd<counter)
                    counter=dd;
            }else
                dfs(xx,yy,dd,n);
            vis[xx][yy]=false;//»ØËÝ
        }
    }
    return counter;
}

int bfs(int x,int y,int n,char c[][maxn])
{
    int counter=0;

    queue<coordinate>q;
    coordinate first={x,y,0};
    vis[x][y]=true;
    q.push(first);
    while(!q.empty())
    {
        coordinate top=q.front();
        q.pop();
        for(int i=0;i<4;i++)
        {
            int xx=top.x+dx[i];
            int yy=top.y+dy[i];
            if(isOk(xx,yy,n,c))
            {
                vis[xx][yy]=true;
                int dd=top.d+1;
                if(dd>counter)
                    counter=dd;
                if(c[xx][yy]=='0')
                    return counter;
                else
                    q.push({xx,yy,dd});
            }
        }
    }
    return counter;
}


int main(){

    int fx=-1;
    int fy=-1;
    cin>>n;
    string str;
    for(int i=0;i<n;i++)
    {
        cin>>str;
        for(int j=0;j<str.length();j++)
        {
            c[i][j]=str[j];
            if(str[j]=='@')
            {
                fx=i;
                fy=j;
            }
        }
    }

    memset(vis,false,sizeof(vis));
    cout<<"dfs:"<<dfs(fx,fy,0,n)<<endl;

    memset(vis,false,sizeof(vis));
    cout<<"bfs:"<<bfs(fx,fy,n,c)<<endl;

    return 0;
}

结果展示:

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转载自blog.csdn.net/Look_star/article/details/107291500