bzoj1054

#include<bits/stdc++.h>
using namespace std;
int f[1<<17],p,q,a[1<<17],dx[4]={1,-1,0,0},dy[4]={0,0,1,-1};
char s[17];
int dfs(int x)
{
    if (x==q)return 0;
    if (f[x])return f[x];
    f[x]=1e9;
    for (int i=0;i<4;i++)
     for (int j=0;j<4;j++)
      if ((x&(1<<(i*4+j)))==(1<<(i*4+j)))
       for (int k=0;k<4;k++)
           {
               int xx=i+dx[k],yy=j+dy[k];
                if (xx>=0&&xx<4&&yy>=0&&yy<4
            &&(x&(1<<(xx*4+yy)))!=(1<<(xx*4+yy)))
               f[x]=min(f[x],dfs((x^(1<<(i*4+j)))|(1<<(xx*4+yy)))+1);
           }
    return f[x];
}
int main()
{
    for (int i=0;i<4;i++)
     {
         scanf("%s",&s);
         for (int j=0;j<4;j++)
          if (s[j]==‘1‘)p+=(1<<(i*4+j));
     }
    for (int i=0;i<4;i++)
     {
         scanf("%s",&s);
         for (int j=0;j<4;j++)
          if (s[j]==‘1‘)q+=(1<<(i*4+j));
     } 
    printf("%d",dfs(p)); 
}