POJ-1163-The Triangle

#include <iostream>
#include <memory.h>
#include <vector>
#include <map>
#include <algorithm>
#include <cstdio>
#include <math.h>
#include <queue>
#include <string>
#include <stack>
#include <iterator>

using namespace std;

typedef long long LL;

const int MAXN = 100 + 10;

int a[MAXN][MAXN];

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

    return 0;
}