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题解：

f[i][j]表示先后手最大差

g[i][j]表示在最大差的时候是否有后手没得走

代码：

#include<bits/stdc++.h>
using namespace std;
const int N=105;
int n,m,q,x,y,a[N][N];
double f[N][N];
char s[105];
int can(int x,int y){return x<=n&&y<=m&&a[x][y]>=0;}
int main()
{
    scanf("%d%d",&n,&m);
    gets(s);
    for (int i=1;i<=n;i++)
     {
        gets(s+1);
        for (int j=1;j<=m;j++)
         {
            if (s[j]=='.')a[i][j]=0;
            if (s[j]=='#')a[i][j]=-1;
            if (s[j]=='H'||s[j]=='C')a[i][j]=1;
            if (s[j]=='F'||s[j]=='S')a[i][j]=3;
            if (s[j]=='I'||s[j]=='B')a[i][j]=5;
         }
     }
    for (int i=n;i;i--)
     for (int j=m;j;j--)
      if (a[i][j]>=0)
       {
        int flag=1;
        double z=-1e10;
        if (can(i,j+1)) flag=0,z=max(z,a[i][j+1]-f[i][j+1]);
        if (can(i+1,j)) flag=0,z=max(z,a[i+1][j]-f[i+1][j]);
        if (can(i+1,j+1)) flag=0,z=max(z,a[i+1][j+1]-f[i+1][j+1]);
        f[i][j]=z;
        if (flag) f[i][j]=-0.5;
       }
    scanf("%d",&q);
    while (q--)
     {
        scanf("%d%d",&x,&y);
        printf("%s\n",f[x][y]>0?"HAL":"DAVE");        
     }
    return 0;
}