Tree Boxes, 2019 US Open Plat

For the Tree Boxes problem: USACO, how do I actually submit my solution? When I submit my code it just terminates on the sample test cases saying

main.cpp:140:10: fatal error: grader.h: No such file or directory
 #include "grader.h"
compilation terminated.

What should I do?

Here’s my code:

Never mind, I figured it out! A C++11 submission works, but a C++17 submission did not work because C++17 was added as an option after the problem was set up.