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/** * The [mode](https://en.wikipedia.org/wiki/Mode_%28statistics%29) is the number * that appears in a list the highest number of times. * There can be multiple modes in a list: in the event of a tie, this * algorithm will return the most recently seen mode. * * This is a [measure of central tendency](https://en.wikipedia.org/wiki/Central_tendency): * a method of finding a typical or central value of a set of numbers. * * This runs in `O(n)` because the input is sorted. * * @param {Array<number>} sorted a sample of one or more data points * @returns {number} mode * @throws {Error} if sorted is empty * @example * modeSorted([0, 0, 1]); // => 0 */function modeSorted(sorted) {    // Handle edge cases:    // The mode of an empty list is undefined    if (sorted.length === 0) {        throw new Error("mode requires at least one data point");    } else if (sorted.length === 1) {        return sorted[0];    }
    // This assumes it is dealing with an array of size > 1, since size    // 0 and 1 are handled immediately. Hence it starts at index 1 in the    // array.    let last = sorted[0],        // store the mode as we find new modes        value = NaN,        // store how many times we've seen the mode        maxSeen = 0,        // how many times the current candidate for the mode        // has been seen        seenThis = 1;
    // end at sorted.length + 1 to fix the case in which the mode is    // the highest number that occurs in the sequence. the last iteration    // compares sorted[i], which is undefined, to the highest number    // in the series    for (let i = 1; i < sorted.length + 1; i++) {        // we're seeing a new number pass by        if (sorted[i] !== last) {            // the last number is the new mode since we saw it more            // often than the old one            if (seenThis > maxSeen) {                maxSeen = seenThis;                value = last;            }            seenThis = 1;            last = sorted[i];            // if this isn't a new number, it's one more occurrence of            // the potential mode        } else {            seenThis++;        }    }    return value;}
export default modeSorted;