1405. 最长快乐字符串.md

1405. 最长快乐字符串

• 贪心算法

/**
 *
 * @description 贪心算法: 每次循环都尽可能去消耗[当前出现]次数最多的字符
 * @see https://leetcode-cn.com/problems/longest-happy-string/comments/329661
 * @param {number} a
 * @param {number} b
 * @param {number} c
 * @return {*}  {string}
 */
function longestDiverseString(a: number, b: number, c: number): string {

    let result: string = ``,
        options: { char: string, count: number }[] = [{
            char: 'a',
            count: a,
        }, {
            char: 'b',
            count: b,
        }, {
            char: 'c',
            count: c,
        }];

    while (true) {
        // 按照数量从大到小排序
        options.sort((a, b) => b.count - a.count);
        const { length } = result;

        for (const option of options) {
            const { char, count } = option;

            if (!count) { // 次数用完了!
                continue;
            }

            if (
                result.length >= 2
                && char === result[result.length - 1]
                && char === result[result.length - 2]
            ) { // 再继续下去,就不能快乐的玩耍了
                continue;
            }

            result += char; 
            --option.count;
            break;
        }

        if (length === result.length) { // 字符串没有累加过,要么没得选(所有的count全为0),要么不能选(再选就要不快乐了),说明没有选择的余地了,只能退出!
            break;
        }
    }

    return result;
};