[BZOJ1088][SCOI2005]扫雷Mine DP

题目链接：http://www.lydsy.com/JudgeOnline/problem.php?id=1088

记录下每一个格子对应左边格子放的雷的情况，然后dp转移就好了。

 #include<cstdio>
 #include<cstring>
 #include<algorithm>
 using namespace std;
 typedef long long ll;
 int inline readint(){
     int Num;char ch;
     while((ch=getchar())<''||ch>'');Num=ch-'';
     while((ch=getchar())>=''&&ch<='') Num=Num*+ch-'';
     return Num;
 }
 int N;
 int a[];
 ll f[][][][];
 int main(){
     N=readint();
     for(int i=;i<=N;i++) a[i]=readint();
     f[][][][]=;
     f[][][][]=;
     for(int i=;i<=N;i++){
         switch(a[i]){
             case :
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 break;
             case :
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 break;
             case :
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 break;
             case :
                 f[i][][][]=f[i-][][][]+f[i-][][][];
                 break;
         }
     }
     ll ans=f[N][][][]+f[N][][][]+f[N][][][]+f[N][][][];
     printf("%lld\n",ans);
     return ;
 }