#include <iostream>#include <stdlib.h>//use recurrence way to find most biggest total using namespace std;int sum=0;void print_value(int a[][110],int N) //printf the number { for(int row=1; row<=N; row++) for(int line=1; line<=row; line++) cin>>a[row][line];}void search(int a[][110], int i, int j, int N, int all) //find the most biggest number{ all+=a[i][j]; if(i==N) { if(sum <all ) sum =all ; return ; } search(a ,i+1 ,j ,N, all); search(a ,i+1 ,j+1 ,N ,all);}int main(){ int N; cin>>N; int value[110][110]={0}; print_value(value,N); search(value ,1 ,1 ,N , 0); cout<<sum<<endl; return 0;}