#include <iostream>

using namespace std;

const int N = 510;

int w[N][N];
int f[N][N];

int main()
{
    int n;
    cin >> n;

    for (int i = 1; i <= n; i ++)
        for (int j = 1; j <= i; j ++ )
            cin >> w[i][j];

    for (int i = 1; i <= n; i ++) f[n][i] = w[n][i];

    for (int i = n - 1; i; i -- )
    {
        for (int j = 1; j <= i; j ++)
        {
            f[i][j] = max(f[i + 1][j - 1], f[i + 1][j]) + w[i][j];
            f[i][j] = max(f[i][j], f[i + 1][j + 1] + w[i][j]);
        }
    }

    cout << f[1][1] << endl;

    return 0;
}

最后的结果应该是23 但是我的代码的结果是26
球球大佬了指点一下。