代码

#include <cstring>
#include <iostream>

using namespace std;

const int N = 5e2 + 10;

int n, m;
int a[N][N], dp[N][N];

int main()
{
    cin >> n;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= i; j++) {
            cin >> a[i][j];
        }
    }

    memset(dp, 0xcf, sizeof dp);

    dp[1][1] = a[1][1];

    for (int i = 2; i <= n; i++) {
        for (int j = 1; j <= i; j++) {
            dp[i][j] = max(dp[i - 1][j - 1], dp[i - 1][j]) + a[i][j];
        }
    }

    int res = 0xcfcfcfcf;

    for (int i = 1; i <= n; i++) {
        res = max(res, dp[n][i]);
    }

    cout << res << endl;

    return 0;
}