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                // 最小硬币找零
    function MinCoinChange(coins) {
      var coins = coins; //{1}该参数代表问题中的面额
      var cache = {}; //{2}为了更加高效且不重复计算值
      this.makeChange = function (amount) {
        var me = this;
        if (!amount) { //{3}若amount不为正(< 0),就返回空数组
          return [];
        if (cache[amount]) { //{4}若结果已缓存,则直接返回结果;否则,执行算法。
          return cache[amount]; 
        var min = [], newMin, newAmount;
        for (var i = 0; i < coins.length; i++) { //{5}
          var coin = coins[i];
          newAmount = amount - coin; //{6},对每个面额,我们都计算newAmount的值,它的值会一直减小,直到能找零的最小钱数
          if (newAmount >= 0) {
            newMin = me.makeChange(newAmount); //{7}
          if (
            newAmount >= 0 && //{8}
            (newMin.length < min.length - 1 || !min.length)//{9}
            && (newMin.length || !newAmount)) //{10} 判断newAmount是否有效,minValue (最少硬币数)是否是最优解,与此同时minValue和newAmount是否是合理的值
            min = [coin].concat(newMin); //{11}有一个比之前更优的答案
            console.log('new Min ' + min + ' for ' + amount);
        console.log(amount, min, 'cache')
        return (cache[amount] = min); //{12}返回最终结果

var minCoinChange = new MinCoinChange([1, 5, 10, 25]);