Function getFrequencyMap

javascript/0076-minimum-window-substring.js:18–24

(str, frequencyMap = new Map())

};

const getFrequencyMap = (str, frequencyMap = new Map()) => {
    for (const char of str) {
        frequencyMap.set(char, (frequencyMap.get(char) || 0) + 1);
    }

    return frequencyMap;
};

const getWindowPointers = (s, t, frequencyMap) => {
    let [left, right, matched, start, end] = [0, 0, 0, 0, s.length + 1];