[WSL] First pass:

> time ./main > /dev/null

real    0m5.825s
user    0m5.094s
sys     0m3.714s

[WSL] After adopting customStringToIntParser: (WSL)

> time ./main > /dev/null

real    0m4.291s
user    0m0.329s
sys     0m3.465s

[Native]

$ time ./main.exe > /dev/null

real    0m2.877s
user    0m0.000s
sys     0m0.000s