方格取数--状压DP or 网络流

题意：http://acm.hdu.edu.cn/showproblem.php?pid=1565

取不相邻的点是权值最大。

这题可以网络流做，暂时先DP一下，网络流明天学一下~~

 #define IOS ios_base::sync_with_stdio(0); cin.tie(0);

 #include <cstdio>//sprintf islower isupper

 #include <cstdlib>//malloc  exit strcat itoa system("cls")

 #include <iostream>//pair

 #include <fstream>//freopen("C:\\Users\\13606\\Desktop\\草稿.txt","r",stdin);

 #include <bitset>

 //#include <map>

 //#include<unordered_map>

 #include <vector>

 #include <stack>

 #include <set>

 #include <string.h>//strstr substr

 #include <string>

 #include <time.h>// srand(((unsigned)time(NULL))); Seed n=rand()%10 - 0~9;

 #include <cmath>

 #include <deque>

 #include <queue>//priority_queue<int, vector<int>, greater<int> > q;//less

 #include <vector>//emplace_back

 //#include <math.h>

 //#include <windows.h>//reverse(a,a+len);// ~ ! ~ ! floor

 #include <algorithm>//sort + unique : sz=unique(b+1,b+n+1)-(b+1);+nth_element(first, nth, last, compare)

 using namespace std;//next_permutation(a+1,a+1+n);//prev_permutation

 //******************

 int abss(int a);

 int lowbit(int n);

 int Del_bit_1(int n);

 int maxx(int a,int b);

 int minn(int a,int b);

 double fabss(double a);

 void swapp(int &a,int &b);

 clock_t __STRAT,__END;

 double __TOTALTIME;

 void _MS(){__STRAT=clock();}

 void _ME(){__END=clock();__TOTALTIME=(double)(__END-__STRAT)/CLOCKS_PER_SEC;cout<<"Time: "<<__TOTALTIME<<" s"<<endl;}

 //***********************

 #define rint register int

 #define fo(a,b,c) for(rint a=b;a<=c;++a)

 #define fr(a,b,c) for(rint a=b;a>=c;--a)

 #define mem(a,b) memset(a,b,sizeof(a))

 #define pr printf

 #define sc scanf

 #define ls rt<<1

 #define rs rt<<1|1

 typedef long long ll;

 const double E=2.718281828;

 const double PI=acos(-1.0);

 //const ll INF=(1LL<<60);

 const int inf=(<<);

 const double ESP=1e-;

 const int mod=(int)1e9+;

 const int N=(int)1e6+;

 int ok_num[N];

 int dp[][];

 int a[][];

 bool OK(int n,int x)

 {

     int F[];

     F[]=;

     for(int i=;i<=n;++i)

         F[i]=(x>>(n-i))&;

     for(int i=;i<n;++i)

         if(F[i]&&F[i+])return ;

     return ;

 }

 int get(int now,int state,int n)

 {

     int F[];

     F[]=;

     for(int i=;i<=n;++i)

         F[i]=(state>>(n-i))&;

     int temp=;

     for(int i=;i<=n;++i)

         if(F[i])temp+=a[now][i];

     return temp;

 }

 void solve(int n)

 {

     int cnt=;

     int tot=(<<n)-;

     for(int i=;i<=tot;++i)

     {

         if(OK(n,i))

             ok_num[++cnt]=i;

     }

 //    cout<<cnt<<endl;

     for(int i=;i<=n;++i)

         for(int j=;j<=n;++j)

             sc("%d",&a[i][j]);

     for(int i=;i<=cnt;++i)

         dp[][i]=dp[][i]=;

     for(int i=;i<=n;++i)

     {

         for(int j=;j<=cnt;++j)

         {

             int temp=get(i,ok_num[j],n);

         //    dp[1][j]=temp;

             for(int k=;k<=cnt;++k)

             {

                 if((ok_num[j]&ok_num[k])==)

                     dp[][j]=maxx(dp[][j],temp+dp[][k]);

             }

         }

         for(int j=;j<=cnt;++j)

             dp[][j]=dp[][j],dp[][j]=;

     }

     int ans=;

     for(int i=;i<=cnt;++i)

         ans=maxx(ans,dp[][i]);

     pr("%d\n",ans);

 }

 int main()

 {

     int n;

     while(~sc("%d",&n))solve(n);

     return ;

 }

 /**************************************************************************************/

 int maxx(int a,int b)

 {

     return a>b?a:b;

 }

 void swapp(int &a,int &b)

 {

     a^=b^=a^=b;

 }

 int lowbit(int n)

 {

     return n&(-n);

 }

 int Del_bit_1(int n)

 {

     return n&(n-);

 }

 int abss(int a)

 {

     return a>?a:-a;

 }

 double fabss(double a)

 {

     return a>?a:-a;

 }

 int minn(int a,int b)

 {

     return a<b?a:b;

 }