poj 1163

# include <cstdio>
# include <cstdlib>
# include <cmath>
# include <cstring>
# include <string>
# include <iostream>
# include <iomanip>
# include <algorithm>
# include <list>
# include <stack>
# include <vector>
# include <queue>
# include <map>
using namespace std;

int dp[103][103];
int a[103][103];

int main()
{
	int n;
	while (cin >> n)
	{
		memset(dp,0,sizeof(dp));
		memset(a, 0, sizeof(a));
		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++)
		{
			dp[n][i] = a[n][i];
		}
		for (int i = n-1; i >= 1; i--)
		{
			for (int j = 1; j <= i; j++)
			{
				dp[i][j] = max(dp[i + 1][j], dp[i + 1][j + 1]) + a[i][j];
			}
		}
		cout << dp[1][1] << endl;

	}

	return 0;
}