Usage:
$ cd 01
$ make test
cat test.txt | cargo run --manifest-path 1/Cargo.toml --quiet
The answer is 24000
cat test.txt | cargo run --manifest-path 2/Cargo.toml --quiet
The answer is 45000
$ make
cat input.txt | cargo run --manifest-path 1/Cargo.toml --quiet
The answer is 71471
cat input.txt | cargo run --manifest-path 2/Cargo.toml --quiet
The answer is 211189