poj1753 flip game题解

来源：互联网发布：生化危机4 知乎编辑：程序博客网时间：2024/05/05 09:43

#include<iostream>
using namespace std;
#include<cmath>
#define MAX 65536
const int a[16]={

0xc800,0xe400,0x7200,0x3100,

0x8c80,0x4e40,0x2720,0x1310,

0x08c8,0x04e4,0x0272,0x0131,

       0x008c,0x004e,0x0027,0x0013,};
int main()
{
int front=0,rear=0;
int levelend=0,levelcount=0;
int flip[MAX],b[MAX]={0};
int i,j,k=0,temp,ni=1;
bool flag=true;
char ch;
for(i=0;i<16;i++)
{
  cin>>ch;
  j=(ch=='b'?1:0);
  k+=(int)j*pow((double)2,15-i);
}
rear=(rear+1)%MAX;
flip[rear]=k;
while(flag&&front<=levelend)
{
  while(front<=levelend)
  {
   front=(front+1)%MAX;
   if(flip[front]==0xffff||flip[front]==0x0000)
   {
    flag=false;
    break;
   }
   for(i=0;i<16;i++)
   {
    temp=flip[front]^a[i];
    if(b[temp]==0)
    {
     rear=(rear+1)%MAX;
     flip[rear]=temp;
     b[temp]=1;
    }
   }
  }
  levelend=rear;
  levelcount++;
}
if(front>levelend)
{
  cout<<"Impossible";
}
else
{
  cout<<levelcount-1;
}
return 0;
}