/
Frequency.re
40 lines (33 loc) · 1.11 KB
/
Frequency.re
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[@bs.val] external __dirname: string = "__dirname";
exception InvalidVarianceString(string);
exception InvalidSign;
let inputFilename = "input.txt";
let getAbsolutePath = (filename: string) =>
Node.Path.resolve(__dirname, filename);
let loadFile = (path: string) => Node.Fs.readFileSync(path, `utf8);
let splitStringContents = string => Js.String.split("\n", string);
let parseVariance = (varianceString: string) => {
let r = [%re "/([+-])(\\d+)/"];
let result = Js.String.match(r, varianceString);
switch (result) {
| Some([|_entire, sign, value|]) =>
switch (sign) {
| "+" => int_of_string(value)
| "-" => int_of_string(value) * (-1)
| _ => raise(InvalidSign)
}
| _ => raise(InvalidVarianceString(varianceString))
};
};
let parseVariances = (varianceStrings: array(string)) =>
Array.map(parseVariance, varianceStrings);
let addVariance = (initial: int, variance: int) => initial + variance;
let addVariances = (variances: array(int)) =>
Array.fold_left(addVariance, 0, variances);
inputFilename
|> getAbsolutePath
|> loadFile
|> splitStringContents
|> parseVariances
|> addVariances
|> Js.log;