NOIp2007 矩阵取数游戏

#include <cstdio>
#include <cstring>
#include <iostream>

const int max_n=80+4;

int N,M;

__int128 Ans;
__int128 A[max_n],dp[max_n][max_n],Pow[max_n];

inline int read()
{
    register int x=0;
    register char ch=getchar();
    while(!isdigit(ch))
        ch=getchar();
    while(isdigit(ch))
    {
        x=(x<<1)+(x<<3)+ch-‘0‘;
        ch=getchar();
    }
    return x;
}

inline void out(__int128 x)
{
    if(x>9) out(x/10);
    putchar(x%10+‘0‘);
}

int main()
{
    N=read(),M=read();
    Pow[0]=1;
    for(int i=1;i<=M;++i)
        Pow[i]=Pow[i-1]<<1;
    while(N--)
    {
        memset(dp,0,sizeof(dp));
        for(int i=1;i<=M;++i)
            A[i]=read();
        for(int l=M;l>=1;--l)
            for(int r=l;r<=M;++r)
                dp[l][r]=std::max(dp[l+1][r]+A[l]*Pow[M-r+l],dp[l][r-1]+A[r]*Pow[M-r+l]);
        Ans+=dp[1][M];
    }
    out(Ans);
    return 0;
}