hdu 2845 Beans

#include<iostream>
#include<cstdio>
#include<algorithm>

using namespace std;

//很多二维的问题能够分解成两个一维的问题

int x[200002], y[200002];

int main()
{
    int n, m, a;
    while (cin>>n>>m) {  //顺手就写成了（cin>>n>>m,n|m）然后就TLE了。。。&_&
        for (int i = 2; i <= n+1; ++i)
        {
            for (int j = 2; j <= m+1; ++j)
            {
                scanf("%d", &a);
                x[j] = max(x[j-1], x[j-2]+a);
            }
            y[i] = max(y[i-1], y[i-2]+x[m+1]);
        }
        cout<<y[n+1]<<endl;
    }
    return 0;
}