https://www.acmicpc.net/problem/1932
#include <iostream>
using namespace std;
int dp[501][501] = { 0, };
int triangle[501][501] = { 0, };
int main(void)
{
	int n, max_val = 0;;
	cin >> n;
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= i; j++)
		{
			cin >> triangle[i][j];
		}
	}
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= i; j++)
		{
			
			dp[i][j] = max(dp[i - 1][j-1], dp[i - 1][j]) + triangle[i][j];
		}
	}
	for (int i = 1; i <= n; i++)
	{
		max_val = max(max_val, dp[n][i]);
	}
	cout << max_val;
	return 0;
}