HDU 3345 War Chess （BFS）

War Chess

Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 32768/32768K (Java/Other)

Total Submission(s) : 7   Accepted Submission(s) : 4

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Problem Description

War chess is hh's favorite game:
In this game, there is an N * M battle map, and every player has his own Moving Val (MV). In each round, every player can move in four directions as long as he has enough MV. To simplify the problem, you are given your position and asked to output which grids you can arrive.

In the map:
'Y' is your current position (there is one and only one Y in the given map).
'.' is a normal grid. It costs you 1 MV to enter in this gird.
'T' is a tree. It costs you 2 MV to enter in this gird.
'R' is a river. It costs you 3 MV to enter in this gird.
'#' is an obstacle. You can never enter in this gird.
'E's are your enemies. You cannot move across your enemy, because once you enter the grids which are adjacent with 'E', you will lose all your MV. Here “adjacent” means two grids share a common edge.
'P's are your partners. You can move across your partner, but you cannot stay in the same grid with him final, because there can only be one person in one grid.You can assume the Ps must stand on '.' . so ,it also costs you 1 MV to enter this grid.

Input

The first line of the inputs is T, which stands for the number of test cases you need to solve.
Then T cases follow:
Each test case starts with a line contains three numbers N,M and MV (2<= N , M <=100,0<=MV<= 65536) which indicate the size of the map and Y's MV.Then a N*M two-dimensional array follows, which describe the whole map.

Output

Output the N*M map, using '*'s to replace all the grids 'Y' can arrive (except the 'Y' grid itself). Output a blank line after each case.

Sample Input

5
3 3 100
...
.E.
..Y

5 6 4
......
....PR
..E.PY
...ETT
....TT

2 2 100
.E
EY

5 5 2
.....
..P..
.PYP.
..P..
.....

3 3 1
.E.
EYE
...

Sample Output

...
.E*
.*Y

...***
..**P*
..E*PY
...E**
....T*

.E
EY

..*..
.*P*.
*PYP*
.*P*.
..*..

.E.
EYE
.*.

Author

shǎ崽

Source

HDU2010省赛集训队选拔赛（校内赛）

题意：

把能走的地方用*标记，输出图。

point：

其他和普通的BFS都差不多！但是，判断附近有没有E的时候要先判断能不能走到那个格子，如果不行还是不能走的。代码写法不同会使题目相对变得复杂T-T，WA了好久。

#include<stdio.h>
#include <queue>
#include <iostream>
#include <string.h>
using namespace std;
const int N =100+5;
char mp[N][N];
int n,m,MV;
int mv[N][N];
int em[N][N];
int dir[4][2]= {0,1,0,-1,1,0,-1,0};
struct node
{
    int x,y;
};
queue<node>q;
void bfs()
{
    while(!q.empty())
    {
        node now=q.front();
        q.pop();
        for(int i=0; i<4; i++)
        {
            int xx=now.x+dir[i][0];
            int yy=now.y+dir[i][1];
            if(xx>n||xx<1||yy>m||yy<1||mp[xx][yy]=='#'||mp[xx][yy]=='E'||mp[xx][yy]=='Y') continue;
            if(mp[xx][yy]=='R')
            {
                if(mv[xx][yy]>=mv[now.x][now.y]-3)continue;
                else mv[xx][yy]=mv[now.x][now.y]-3;
            }
            else if(mp[xx][yy]=='T')
            {
                if(mv[xx][yy]>=mv[now.x][now.y]-2)continue;
                else   mv[xx][yy]=mv[now.x][now.y]-2;
            }
            else if(mp[xx][yy]=='.'||mp[xx][yy]=='P')
            {
                if(mv[xx][yy]>=mv[now.x][now.y]-1)continue;
                else   mv[xx][yy]=mv[now.x][now.y]-1;
            }
            if(mv[xx][yy]<=0) continue;
            if(em[xx][yy]==1)
            {
                if(mv[xx][yy]>=0) //因为缺少这句话WA了一小时。
                    mv[xx][yy]=0;
                continue;
            }
            node keep;
            keep.x=xx;
            keep.y=yy;
            q.push(keep);
        }
    }
}
int main()
{
    int t;
    scanf("%d",&t);
    while(t--)
    {
        memset(mv,-1,sizeof mv);
        memset(mp,0,sizeof mp);
        memset(em,0,sizeof em);
        scanf("%d %d %d",&n,&m,&MV);
        int bi,bj;
        for(int i=1; i<=n; i++)
        {
            getchar();
            for(int j=1; j<=m; j++)
            {
                scanf("%c",&mp[i][j]);
                if(mp[i][j]=='Y')
                {
                    mv[i][j]=MV;
                    bi=i;
                    bj=j;
                }
                else if(mp[i][j]=='E')
                {
                    if(i+1<=n) em[i+1][j]=1;
                    if(i-1>=1) em[i-1][j]=1;
                    if(j+1<=m) em[i][j+1]=1;
                    if(j-1>=1) em[i][j-1]=1;
                }
            }
        }
        while(!q.empty()) q.pop();
        node b;
        b.x=bi;
        b.y=bj;
        q.push(b);
        bfs();
        for(int i=1; i<=n; i++)
        {
            for(int j=1; j<=m; j++)
            {
                if(mv[i][j]>=0)
                {
                    if(mp[i][j]=='P'||mp[i][j]=='Y'||mp[i][j]=='#') printf("%c",mp[i][j]);
                    else printf("*");
                }
                else
                    printf("%c",mp[i][j]);
            }
            printf("\n");
        }
        printf("\n");
    }

    return 0;
}

代码写的很丑，可以改的更短一点。