#include <iostream>
#include <vector>
#include <algorithm>

int main()
{
    std::vector<std::vector<std::size_t>> t
    {
        {75},
        {95, 64},
        {17, 47, 82},
        {18, 35, 87, 10},
        {20,  4, 82, 47, 65},
        {19,  1, 23, 75,  3, 34},
        {88,  2, 77, 73,  7, 63, 67},
        {99, 65,  4, 28,  6, 16, 70, 92},
        {41, 41, 26, 56, 83, 40, 80, 70, 33},
        {41, 48, 72, 33, 47, 32, 37, 16, 94, 29},
        {53, 71, 44, 65, 25, 43, 91, 52, 97, 51, 14},
        {70, 11, 33, 28, 77, 73, 17, 78, 39, 68, 17, 57},
        {91, 71, 52, 38, 17, 14, 91, 43, 58, 50, 27, 29, 48},
        {63, 66,  4, 68, 89, 53, 67, 30, 73, 16, 69, 87, 40, 31},
        { 4, 62, 98, 27, 23,  9, 70, 98, 73, 93, 38, 53, 60,  4, 23}
    };

    for(auto l = t.rbegin() + 1; l != t.rend(); ++l)
    {
        for(std::size_t i = 0; i < l->size(); ++i)
        {
            l->at(i) += std::max((l - 1)->at(i), (l - 1)->at(i + 1));
        }
    }

    std::cout << t.at(0).at(0) << std::endl;

    return 0;
}