POJ 1157

#include<iostream>  //成大才子---经典代码~
#include<stdio.h>
#include<algorithm>
#define MAXN 150
using namespace std;

int _m[MAXN][MAXN];
int main()
{
    //freopen("acm.acm","r",stdin);
    int r;
    int c;
    int i;
    int j;
    int maxn;
    cin>>r>>c;
    for(i = 0; i < r; ++ i)
        for(j = 0; j < c; ++ j)
            cin >> _m[i][j];
    for(i = r-1; i > 0; -- i)
        for(j = i; j < c-(r-1-i); ++ j)
        {
            _m[i][j] = *max_element(_m[i]+j,_m[i]+c-(r-1-i));
            _m[i-1][j-1] += _m[i][j]; 
        }
    maxn = * max_element(_m[0],_m[0]+c-r+1);
    cout<<maxn<<endl;
}