> #include<iostream>
> using namespace std;
> int main()
> {
> 	int n,i,j,a[100][100];
> 	cin>>n;
> 	for(i=1;i<=n;i++)
> 	{
> 		for(j=1;j<=i;j++)
> 		{
> 			cin>>a[i][j];
> 		}
> 	}
> 	for(i=n-1;i>=1;i--)
> 	{
> 		for(j=1;j<=i;j++)
> 		{
> 			a[i][j]=((a[i][j]+a[i+1][j])>(a[i][j]+a[i+1][j+1]))?
> 				(a[i][j]+a[i+1][j]):(a[i][j]+a[i+1][j+1]);
> 		}
> 	}
> 	cout<<a[1][1]<<endl;
> 	return 0;
> }