hdu2612 Find a way

广搜两遍找出Y和M到每个KFC的最短距离，然后找一个和最小的输出……

本来打算两个人一起走，碰头就输出。

结果发现如果最短距离的KFC离某一个人很近，但离另一个很远，而又有一个KFC在两人之间的时候，答案就不对了。

结果只能用这种笨办法了。

#include <stdio.h>
#include <string.h>
#define INF 9999
typedef struct{
    int x,y,t;
}QUEUE;
char map[203][203];
const int dirc[4][2] = {{0,1},{0,-1},{1,0},{-1,0}};
int n,m,yVisit[203][203],mVisit[203][203];
QUEUE q1[80000],q2[80000];

int logic(int x, int y){
    return (x>=0&&y>=0&&x<n&&y<m&&map[x][y]!='#');
}
int bfs(int yStrX, int yStrY, int mStrX, int mStrY){
    int yTop,yTail,mTop,mTail,yTime,mTime,i;
    int yNextX,yNextY,yNextTime,mNextX,mNextY,mNextTime;
    yTop = yTail = mTop = mTail = 0;
    q1[yTail].x = yStrX;
    q1[yTail].y = yStrY;
    q1[yTail++].t = 0;
    yVisit[yStrX][yStrY] = 1;
    q2[mTail].x = mStrX;
    q2[mTail].y = mStrY;
    q2[mTail++].t = 0;
    mVisit[mStrX][mStrY] = 1;
    while(yTop < yTail || mTop < mTail){
        if(yTop < yTail){
            yStrX = q1[yTop].x;
            yStrY = q1[yTop].y;
            yTime = q1[yTop++].t;
            for(i = 0; i < 4; i++){
                yNextX = yStrX + dirc[i][0];
                yNextY = yStrY + dirc[i][1];
                yNextTime = yTime + 1;
                if(logic(yNextX,yNextY) && !yVisit[yNextX][yNextY]){
                    yVisit[yNextX][yNextY] = yNextTime;
                    q1[yTail].x = yNextX;
                    q1[yTail].y = yNextY;
                    q1[yTail++].t = yNextTime;
                }
            }
        }
        if(mTop < mTail){
            mStrX = q2[mTop].x;
            mStrY = q2[mTop].y;
            mTime = q2[mTop++].t;
            for(i = 0; i < 4; i++){
                mNextX = mStrX + dirc[i][0];
                mNextY = mStrY + dirc[i][1];
                mNextTime = mTime + 1;
                if(logic(mNextX,mNextY) && !mVisit[mNextX][mNextY]){
                    mVisit[mNextX][mNextY] = mNextTime;
                    q2[mTail].x = mNextX;
                    q2[mTail].y = mNextY;
                    q2[mTail++].t = mNextTime;
                }
            }        
        }
    }
    return 0;
}
int main (void){
    int i,j,yStrX,yStrY,mStrX,mStrY,min;
    while(~scanf("%d%d",&n,&m)){
        getchar();
        memset(yVisit,0,sizeof(yVisit));
        memset(mVisit,0,sizeof(mVisit));
        for(i = 0; i < n; i++){
            gets(map[i]);
            for(j = 0; j < m; j++){
                if(map[i][j] == 'Y'){
                    yStrX = i;
                    yStrY = j;
                }
                else if(map[i][j] == 'M'){
                    mStrX = i;
                    mStrY = j;
                }
            }
        }
        bfs(yStrX,yStrY,mStrX,mStrY);
        min = INF;
        for(i = 0; i < n; i++)
            for(j = 0; j < m; j++){
                if(map[i][j] == '@' && yVisit[i][j] && mVisit[i][j])
                    if(min > yVisit[i][j] + mVisit[i][j])
                        min = yVisit[i][j] + mVisit[i][j];
            }
        printf("%d\n",min * 11);
    }
    return 0;
}