BFS

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAXN 100

int maze[MAXN][MAXN];
int vis[MAXN][MAXN];
int queue[MAXN*MAXN];   //队列
int fa[MAXN][MAXN]; // 父结点
int dx[]={0,0,-1,1};
int dy[]={-1,1,0,0};

int n,m;    //n为行 m为列

void bfs(int x, int y){
    int front, rear, u, d;
    front = rear = 0;
    u = x*m+y;
    queue[rear++] = u;
    vis[x][y] = 1; fa[x][y] = u;    //起点的父结点为它本身
    while(front < rear){
        u = queue[front++];
        x = u/m; y = u%m;
        for(d=0; d<4; d++){
            int nx = x+dx[d]; int ny = y+dy[d];
            if(nx >=0 && nx <n && ny >=0 && ny < m && !vis[nx][ny] && maze[nx][ny]){
                int v = nx*m+ny;
                fa[nx][ny]=u; queue[rear++]=v;
                vis[nx][ny]=1;
                if(nx == n-1 && ny == m-1) return ;
            }
        }
    }
}

void print_path(int x, int y){  //从终点
    int nx = fa[x][y] / m;
    int ny = fa[x][y] % m;
    if(nx != x || ny != y){
        print_path(nx, ny);
        printf("(%d,%d)->(%d,%d)\n", nx, ny, x, y);
    }
}

int main ( ){
    freopen("d:\\my.txt", "r", stdin);
    memset(vis, 0, sizeof(vis));    memset(maze, 0, sizeof(maze));
    int i,j;
    scanf("%d %d", &n, &m);
    for(i=0; i<n; i++)
        for(j=0; j<m; j++)
            scanf("%d", &maze[i][j]);
    bfs(0,0);
    print_path(n-1, m-1);
    return 0;
}
原文地址:https://www.cnblogs.com/tanhehe/p/2883512.html