#include <iostream>#include <string.h>using namespace std;int max(int a, int b){ return a>b?a:b;}int main(){ int f,v; int a[105][105]; int ans[105][105]; memset(ans,0,sizeof(ans)); cin>>f>>v; for(int i=1;i<=f;i++) { for(int j=1;j<=v;j++) { cin>>a[i][j]; } ans[i][i]=ans[i-1][i-1]+a[i][i]; } for(int i=1;i<=f;i++) { for(int j=i+1;j<=v;j++)//注意这里是j=i+1，j不可以从i开始 { ans[i][j]=max(ans[i][j-1],ans[i-1][j-1]+a[i][j]); } } cout<<ans[f][v]<<endl; return 0;}
