剑指67/JZ32把数组排成最小的数.html

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    <script>
      // 题目描述
      // 输入一个正整数数组，把数组里所有数字拼接起来排成一个数，打印能拼接出的所有数字中最小的一个。
      // 例如输入数组{3，32，321}，则打印出这三个数字能排成的最小数字为321323。

      // 1 输出全排列 求最小值 复杂度太高

      // 没怎么理解
      function PrintMinNumber(numbers) {
        const tmpArr = [],
          count = [];
        if (numbers.length < 2) {
          return numbers[0] || '';
        }
        PrintNumber('');
        function PrintNumber1(str) {
          if (str.length === numbers.join('').length) {
            tmpArr.push(Number(str));
            return false;
          }
          for (let i = 0; i < numbers.length; i++) {
            if (!count[i]) {
              count[i] = true;
              PrintNumber(str + numbers[i]);
              count[i] = false;
            }
          }
        }

        return Math.min(...tmpArr);
      }

      // 类似选择排序 把太大的放后面
      function PrintMinNumber(numbers) {
        if (numbers == null || numbers.length == 0) return '';
        for (let i = 0; i < numbers.length; i++) {
          for (let j = i + 1; j < numbers.length; j++) {
            let sum1 = Number(numbers[i] + '' + numbers[j]);
            let sum2 = Number(numbers[j] + '' + numbers[i]);
            if (sum1 > sum2) {
              let temp = numbers[j];
              numbers[j] = numbers[i];
              numbers[i] = temp;
            }
          }
        }
        let str = '';
        for (let i = 0; i < numbers.length; i++) str = str + numbers[i];
        return str;
      }

      const input = [3, 32, 321];
      console.log(`input: ${input} , expect: 321323 => PrintMinNumber `, PrintMinNumber(input));
    </script>
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