NYOJ--284--广搜+优先队列--坦克大战

/*
	Name: NYOJ--284--坦克大战
	Author: shen_渊 
	Date: 14/04/17 19:08
	Description: 广度优先搜索+优先队列
				注意清空地图 
				对输入地图进行了预处理，将S，R设置为# 
*/

#include 
#include 
#include
using namespace std;
const char YOU = 'Y';
const char TARGET = 'T';
const char RIVER = 'R' ;
const char SWALL = 'S';
const char BWALL = 'B';
const char EMPOTY = 'E';
const char FORBID = '#';
struct node{
	int x,y,steps;
	node():steps(0){};
	bool operator <(const node &a)const{
		return steps>a.steps;	
	}
}you,target;
int bfs();
int check(char);
char map[305][305] = {0};
int m,n;
int dir[4][2] = {{0,1},{0,-1},{1,0},{-1,0}};
int main()
{
//	ios::sync_with_stdio(false);
//	freopen("in.txt","r",stdin);

	while(cin>>m>>n, m || n) {
		int i,j;
		memset(map,0,sizeof(map));
		for(i=1; i<=m; ++i){
			for(j=1; j<=n; ++j){
				cin>>map[i][j];
				switch(map[i][j]){
					case YOU:{
						you.x = i;you.y = j;
						break;
					}
					case TARGET:{
						target.x = i;target.y = j;
						break;
					}
					case RIVER: 
					case SWALL:{
						map[i][j] =='#';
						break;
					}	
					default:break;
				}
			}
		}
		cout< Q;
	while(!Q.empty())Q.pop();
	Q.push(you);
	map[you.x][you.y] = '#';
	while(!Q.empty()){
		node p = Q.top();Q.pop();
		int i,j;
		for(i=0; i<4; ++i){
			node a;
			a.x = p.x + dir[i][0];
			a.y = p.y + dir[i][1];
			if(a.x<1|| a.y<1|| a.x>m|| a.y>n)continue;
			int next;
			if(next = check(map[a.x][a.y])){
				a.steps = p.steps + next;
				if(a.x == target.x && a.y == target.y)return a.steps;
				Q.push(a);
				map[a.x][a.y] = '#';
			}
		}
	}
	return -1;
}
int check(char ch){
	switch(ch){
		case TARGET:return 1;
		case EMPOTY:return 1; 
		case BWALL:return 2;
	}
	return 0;
}