POJ-3984

#include <iostream>
#include <cstdio>
#include <queue>
#include <stack>
#include <cstring>
using namespace std;

int dist[4][2] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
struct _Node{
    int x, y;
    _Node(){
    }
    _Node(int _x, int _y)
    {
        x = _x; y = _y;
    }
};

_Node path[10][10];
int maze[10][10];
int visit[10][10];
stack<_Node> s;

void INIT(){
    memset(maze, 1, sizeof(maze));
    memset(visit, 0, sizeof(visit));
}

void bfs(_Node start)
{
    queue<_Node> q;
    q.push(start);
    visit[start.x][start.y] = 1;
    path[start.x][start.y].x = path[start.x][start.y].y = -1;

    while(!q.empty())
    {
        _Node u = q.front(); q.pop();

        if(u.x == 5 && u.y == 5)
        {
            int x = u.x, y = u.y;
            while(path[x][y].x != -1 && path[x][y].y != -1)
            {
                s.push(path[x][y]);
                int xx = x;
                x = path[x][y].x;
                y = path[xx][y].y;
            }
            while(!s.empty())
            {
                printf("(%d, %d)\n", s.top().x - 1, s.top().y - 1);
                s.pop();
            }
            printf("(4, 4)\n");
        }

        for(int i = 0; i < 4; ++i){
            int dx = u.x + dist[i][0], dy = u.y + dist[i][1];

            if(!visit[dx][dy] && !maze[dx][dy])
            {
                q.push(_Node(dx, dy));
                visit[dx][dy] = 1;
                path[dx][dy].x = u.x;
                path[dx][dy].y = u.y;
             } 
        }
    }
}
int main()
{
    INIT();
    for(int i = 1; i <= 5; ++i)
        for(int j = 1; j <= 5; ++j) cin >> maze[i][j];
    bfs(_Node(1, 1));
    return 0;
}