NYOJ1100WAJUEJI which home strong！

题目链接：http://acm.nyist.net/JudgeOnline/problem.php?pid=1100

BFS + 优先队列！ 自定义优先级！！！！！

代码：

#include <cstdio>
#include <queue>
#include <cstring>

using namespace std;

typedef struct Node
{
    int x,y;
    char c;
    int cost;
} Node;
struct cmp
{
    bool operator()(Node a,Node b)
    {
        return a.cost > b.cost;
    }
};
int dx[] = {-1,0,1,0};
int dy[] = {0,1,0,-1};

char s[105][105];
bool v[105][105];
int stx,sty,enx,eny;
int flag;
int n,m;
priority_queue<Node,vector<Node>,cmp> pq;

int bfs(int x,int y)

{
    Node first;
    first.x = x;
    first.y = y;
    first.c = 's';
    first.cost = 0;
    pq.push(first);
    while(!pq.empty())
    {
        Node head = pq.top();
        //printf("%d %d\n",head.x,head.y);
        pq.pop();
        for(int i = 0; i < 4; ++i)
        {
            Node t;
            t.x = head.x + dx[i];
            t.y = head.y + dy[i];
            t.c = s[t.x][t.y];
            if(t.x == enx && t.y == eny)
            {
                flag = 1;
                return head.cost;
                break;
            }
            if(t.x>=0&&t.x<n&&t.y>=0&&t.y<m&&t.c!='#' && !v[t.x][t.y])
            {
                v[t.x][t.y] = true;
                t.cost = head.cost + (t.c - 'A' + 1);
                pq.push(t);
            }
        }
        if(flag)
            break;
    }
    return -1;
}
void clear()

{
    while(!pq.empty())
        pq.pop();
}
int main()

{
    int _;
    scanf("%d",&_);

    while(_--)
    {
        memset(v,false,sizeof v);
        scanf("%d%d",&n,&m);
        for(int i = 0; i < n; ++i)
            scanf("%s",s[i]);
        for(int i = 0; i < n; ++i)
            for(int j = 0; j < m; ++j)
                if(s[i][j] == 's')
                {
                    stx = i;
                    sty = j;
                }
                else if(s[i][j] == 'l')
                {
                    enx = i;
                    eny = j;
                }
        flag = 0;
        v[stx][sty] = true;
        int ans = bfs(stx,sty);
        printf("%d\n",ans);
        clear();
    }
    return 0;
}