hdu 1242 BFS

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

typedef struct{
int x, y;
int time;
}Node;

int N, M;
int moves[4][2] = { 1, 0, -1, 0, 0, -1, 0, 1 };
int map[200][200];
bool visit[200][200];
vector<Node> friends;
Node angle;

void init(){
memset( visit, false, sizeof( visit ) );
friends.clear();
}

int BFS( Node start ){
memset( visit, false, sizeof( visit ) );
queue<Node> q;
start.time = 0;
q.push( start );

while( !q.empty() ){
Node n = q.front();
q.pop();

for( int i = 0; i < friends.size(); i++ ){
if( n.x == friends[i].x && n.y == friends[i].y ){
return n.time;
}
}

for( int i = 0; i < 4; i++ ){
Node temp = n;
temp.x += moves[i][0];
temp.y += moves[i][1];
if( temp.x < 0 || temp.x >= N || temp.y < 0 || temp.y >= M ){
continue;
}
if( map[temp.x][temp.y] == 0 ){
continue;
}
if( visit[temp.x][temp.y] == true ){
continue;
}
temp.time += map[temp.x][temp.y];
visit[temp.x][temp.y] = true;
q.push( temp );
}
}

return -1;
}

int main(){
char s[201];

while( scanf( "%d%d", &N, &M ) != EOF ){

init();

for( int i = 0; i < N; i++ ){
scanf( "%s", s );
for( int j = 0; j < M; j++ ){
if( s[j] == 'r' ){
map[i][j] = 1;
Node temp;
temp.x = i;
temp.y = j;
friends.push_back( temp );
}else if( s[j] == '.' ){
map[i][j] = 1;
}else if( s[j] == 'x' ){
map[i][j] = 2;
}else if( s[j] == 'a' ){
map[i][j] = 1;
angle.x = i;
angle.y = j;
}else{
map[i][j] = 0;
}
}
}

int ans = BFS( angle );
if( ans != -1 ){
cout << ans << endl;
}else{
cout << "Poor ANGEL has to stay in the prison all his life." << endl;
}
}
return 0;
}