HDU 4901 the romantic hero

Http://acm.hdu.edu.cn/showproblem.php? PID = 1, 4901

Dp1 [I] [J] is the number of I-participating, exclusive OR value J, x1 [I] [J] is the number of different or values from the position I forward to the position 1 as J. dp2 [I] [J] is an I-participated, the value is the number of J, and the value of X2 [I] [J] is the number of J from the position I to the position n.

 1 #include <cstdio> 2 #include <cstring> 3 #include <algorithm> 4 #define ll __int64 5 using namespace std; 6 const int mod=1000000007; 7  8 ll dp1[1100][1100]; 9 ll dp2[1100][1100];10 ll x1[1100][1100];11 ll x2[1100][1100];12 int t,n;13 int c[1100];14 15 int main()16 {17     scanf("%d",&t);18     while(t--)19     {20         scanf("%d",&n);21         for(int i=1; i<=n; i++)22         {23             scanf("%d",&c[i]);24         }25         memset(dp1,0,sizeof(dp1));26         memset(dp2,0,sizeof(dp2));27         memset(x1,0,sizeof(x1));28         memset(x2,0,sizeof(x2));29         for(int i=1; i<=n; i++)30         {31             for(int j=0; j<=1024; j++)32             {33                 int m=j^c[i];34                 dp1[i][m]=(dp1[i][m]+x1[i-1][j])%mod;35             }36             dp1[i][c[i]]=(dp1[i][c[i]]+1)%mod;37             for(int j=0; j<=1024; j++)38             {39                 x1[i][j]=(x1[i-1][j]+dp1[i][j])%mod;40             }41         }42         for(int i=n; i>=1; i--)43         {44             for(int j=0; j<=1024; j++)45             {46                 int m=j&c[i];47                 dp2[i][m]=(dp2[i][m]+x2[i+1][j])%mod;48             }49             dp2[i][c[i]]=(dp2[i][c[i]]+1)%mod;50             for(int j=0; j<=1024; j++)51             {52                 x2[i][j]=(x2[i+1][j]+dp2[i][j])%mod;53             }54         }55         ll ans=0,sum;56         for(int i=1; i<=n-1; i++)57         {58             for(int j=0; j<=1024; j++)59             {60                 sum=(dp1[i][j]*x2[i+1][j])%mod;61                 ans=(ans+sum)%mod;62             }63         }64         printf("%I64d\n",ans);65     }66     return 0;67 }

View code