ZOJ 1649 Rescue

//http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=1649#include <iostream>#include <cstdio>#include <vector>#include <cstring>#include <cctype>#include <algorithm>#include <cmath>#include <cstdlib>#include <queue>#include <map>#define maxn 200 + 10#define INF 0x7fffffffusing namespace std;char g[maxn][maxn];int stx, sty;bool vis[maxn][maxn];int move[4][2] = {0, 1, 0, -1, 1, 0, -1, 0};int n, m;struct POINT{    int cur;    int x, y;};priority_queue<POINT> q;bool operator<(POINT a, POINT b){    return a.cur > b.cur;}int bfs(){    POINT tmp;    memset(vis, false, sizeof(vis));    tmp.x = stx;    tmp.y = sty;    tmp.cur = 0;    vis[stx][sty] = true;    q.push(tmp);    while(!q.empty())    {        tmp = q.top();        q.pop();        for(int i = 0; i < 4; ++i)        {            int dcur = tmp.cur;            int dx = tmp.x + move[i][0];            int dy = tmp.y + move[i][1];            if(dx >= 0 && dx < n && dy >= 0 && dy < m && g[dx][dy] != '#' && !vis[dx][dy])            {                vis[dx][dy] = true;                if(g[dx][dy] == 'a')                    return dcur+1;                else if(g[dx][dy] == '.')                {                    POINT t;                    t.cur = dcur+1;                    t.x = dx;                    t.y = dy;                    q.push(t);                }                else if(g[dx][dy] == 'x')                {                    POINT t;                    t.cur = dcur+2;                    t.x = dx;                    t.y = dy;                    q.push(t);                }            }        }    }    return -1;}int main(){    while(scanf("%d%d", &n, &m) != EOF)    {        while(!q.empty())            q.pop();        memset(vis, false, sizeof(vis));        for(int i = 0; i < n; ++i)        {            scanf("%s", g[i]);            for(int j = 0; j < m; ++j)                if(g[i][j] == 'r')                    stx = i, sty = j;        }        int ans = bfs();        if(ans == -1) puts("Poor ANGEL has to stay in the prison all his life.");        else printf("%d\n", ans);    }    return 0;}