BFS(广度优先搜索算法)——最短路线问题

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#include<stdio.h>

/*有8个城市，编号分别为0~7，求从0号城市到7号城市的最短路线*/
int jz[8][8]= { {0,1,1,1,0,1,0,0},
                {1,0,0,0,0,1,0,0},
                {1,0,0,1,1,0,0,0},
                {1,0,1,0,0,0,1,0},
                {0,0,1,0,0,0,1,1},
                {1,1,0,0,0,0,0,1},
                {0,0,0,1,1,0,0,1},
                {0,0,0,0,1,1,1,0}};//0表示不能走，1表示可行


struct
{
  int city,pre;
} sq[100];

int qh,qe,i,visited[100];

void out()
{
    printf("%d",sq[qe].city);
    while(sq[qe].pre!=0)
    {
        qe=sq[qe].pre;
        printf("--%d",sq[qe].city);
    }
}

void search(int n)
{
    qh=0;
    qe=1;
    sq[1].city=0;
    sq[1].pre=0;
    visited[1]=1;
    while(qh!=qe)   //当队不为空
    {
        qh=qh+1;    //结点出队
        for(i=0;i<n;i++)
            if(jz[sq[qh].city][i]==1&&visited[i]==0)  //如果从城市sq[qh].city可以直接到达城市i，且城市i没有访问过
             {
                 qe=qe+1;//结点入队
                 sq[qe].city=i;
                 sq[qe].pre=qh;
                 visited[i]=1;
                 if(sq[qe].city==7)
                 {
                     out();
                     return ;
                 }
             }

    }
    printf("No Solution!\n");
}

int main()
{
    int i,n;
    n=8;
    for(i=0;i<n;i++)
        visited[i]=0;
    search(n);

    return 0;
}

 

 

 

 

 

 

 

 

运行效果图：

/*迷宫如下，1表示墙，0表示路
0 0 0 0 0 0 0 0
0 1 1 1 1 0 1 0
0 0 0 0 1 0 1 0
0 1 0 0 0 0 1 0
0 1 0 1 1 0 1 0
0 1 0 0 0 0 1 1
0 1 0 0 1 0 0 0
0 1 1 1 1 1 1 0
*/


#include<stdio.h>
/*储存迷宫矩阵*/
int maze[8][8]={{0,0,0,0,0,0,0,0},
                {0,1,1,1,1,0,1,0},
                {0,0,0,0,1,0,1,0},
                {0,1,0,0,0,0,1,0},
                {0,1,0,1,1,0,1,0},
                {0,1,0,0,0,0,1,1},
                {0,1,0,0,1,0,0,0},
                {0,1,1,1,1,1,1,0}};

/*定义方向数组，如：i+fx[0],j+fy[0],表示向下移动*/

int fx[4]={1,-1,0,0};
int fy[4]={0,0,-1,1};

struct {
  int x,y,pre;
}sq[100];


int qh,qe,i,j,k;

void out()
{
    printf("(%d,%d)",sq[qe].x,sq[qe].y);
    while(sq[qe].pre!=0)
    {
        qe=sq[qe].pre;
        printf("--(%d,%d)",sq[qe].x,sq[qe].y);
    }
}
int check(int i,int j)
{
    int flag=1;
    if(i<0||i>7||j<0||j>7)//是否在迷宫内
        flag=0;
    if(maze[i][j]==1||maze[i][j]==-1) //是否可行
       flag=0;
    return flag;
}

void search()
{
    qh=0;
    qe=1;
    maze[0][0]=-1;//表示访问过
    sq[1].pre=0;
    sq[1].x=0;
    sq[1].y=0;
    while(qh!=qe)//当队不为空
    {
        qh=qh+1; //出队
        for(k=0;k<4;k++)//搜索可达到的方块
        {
            i=sq[qh].x+fx[k];
            j=sq[qh].y+fy[k];
            if(check(i,j)==1)
            {
                qe=qe+1;//入队
                sq[qe].x=i;
                sq[qe].y=j;
                sq[qe].pre=qh;
                maze[i][j]=-1;//表示访问过
                if(sq[qe].x==7&&sq[qe].y==7)
                {
                    out();
                    return ;
                }

            }
        }
    }
    printf("No Solution!\n");
}
int main()
{
    search();
    return 0;
}

运行效果图：

PS:每天学到一点点，就很开心