【洛谷P1541】乌龟棋

四维dp

 #include<cstdio>
 #include<cstring>
 using namespace std;
 const int N=;
 int f[N][N][N][N],g[],a,b,c,d,n,m;
 int max(int x,int y){
     return x>y?x:y;
 }
 int main(){
     int tmp;
     a=b=c=d=;
     scanf("%d %d",&n,&m);
     for (int i=;i<=n;i++)
         scanf("%d",&g[i]);
     for (int i=;i<=m;i++){
         scanf("%d",&tmp);
         if (tmp==) a++;
         if (tmp==) b++;
         if (tmp==) c++;
         if (tmp==) d++;
     }
     f[][][][]=g[];
     for (int i=;i<=a;i++)
     for (int j=;j<=b;j++)
     for (int k=;k<=c;k++)
     for (int l=;l<=d;l++){
         tmp=+i+j*+k*+l*;//**
         if (i->=)
             f[i][j][k][l]=max(f[i-][j][k][l]+g[tmp],f[i][j][k][l]);
         if (j->=)
             f[i][j][k][l]=max(f[i][j-][k][l]+g[tmp],f[i][j][k][l]);
         if (k->=)
             f[i][j][k][l]=max(f[i][j][k-][l]+g[tmp],f[i][j][k][l]);
         if (l->=)
             f[i][j][k][l]=max(f[i][j][k][l-]+g[tmp],f[i][j][k][l]);
     }
     printf("%d",f[a][b][c][d]);
     return ;
 }

STD