#include<bits/stdc++.h>
using namespace std;
int a[105][105];
int main()
{
int n;
cin>>n;
for(int i=1;i<=n;i++)
{
for(int j=1;j<=i;j++)
{
cin>>a[i][j];
}
}
for(int i=1;i<=n;i++)
{
for(int j=1;j<=n;j++)
{
cout<<a[i][j]<<" ";
}
cout<<endl;
}
for(int i=n-1;i>=1;i--)
{
for(int j=1;j<=i;j++)
{
if(a[i+1][j]>=a[i+1][j+1])
{
a[i][j]+=a[i+1][j];
}
else
{
a[i][j]+=a[i+1][j+1];
}
}
}
cout<<a[1][1];
return 0;
}
/**************************************************************
Problem: 1216
User: chenkexin
Language: C++
Result: Output Limit Exceed
****************************************************************/