leetCode/1556.千位分隔数.html

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    <title>1556. 千位分隔数</title>
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  <body>
    <script>
      // https://leetcode.cn/problems/thousand-separator/

      // 给你一个整数 n，请你每隔三位添加点（即 "." 符号）作为千位分隔符，并将结果以字符串格式返回。
      // 提示：
      // 0 <= n < 2^31

      /**
       * @param {number} n
       * @return {string}
       */
      var thousandSeparator = function (n) {};

      // --- answer-1 ---

      var thousandSeparator = function (n) {
        let count = 0;
        let ans = '';
        do {
          let cur = n % 10;
          n = Math.floor(n / 10);
          ans += cur.toString();
          ++count;
          if (count % 3 == 0 && n) {
            ans += '.';
          }
        } while (n);
        return ans.split('').reverse().join('');
      };

      // --- answer-1 ---

      // --- answer-2 ---

      // 正则
      var thousandSeparator = function (n) {
        return n.toLocaleString().replace(/\,/g, '.');
      };

      var thousandSeparator = function (n) {
        return String(n).replace(/(?!^)(?=(\d{3})+$)/g, '.');
      };

      // --- answer-2 ---

      // var n = 987;
      // var result = "987";

      // var n = 1234;
      // var result = "1.234";

      // var n = 123456789;
      // var result = "123.456.789";

      // var n = 0;
      // var result = "0";

      console.log('n = ', n);
      console.log('result = ', result);
      console.log('thousandSeparator = ', thousandSeparator(n));
    </script>
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