面试题 05. 替换空格

输入：s = "We are happy."
输出："We%20are%20happy."

class Solution:
    def replaceSpace(self, s: str) -> str:
        return s.replace(' ', '%20')

class Solution {
    public String replaceSpace(String s) {
        return s.replaceAll(" ", "%20");
    }
}

class Solution {
    public String replaceSpace(String s) {
        StringBuilder sb = new StringBuilder();
        char[] chars = s.toCharArray();
        for (char c : chars) {
            sb.append(c == ' ' ? "%20" : c);
        }
        return sb.toString();
    }
}

/**
 * @param {string} s
 * @return {string}
 */
var replaceSpace = function (s) {
  return s.split(" ").join("%20");
};

/**
 * @param {string}
 * @return {string}
 */
var replaceSpace = function(s) {
  s = s.split("");
  let emptyNum = 0;
  for (let i = 0; i < s.length; i++) {
    if (s[i] === " ") {
      emptyNum++;
    }
  }
  let p1 = s.length - 1;
  let p2 = p1 + 2 * emptyNum;
  while (p1 >= 0 && p2 > p1) {
    if (s[p1] === " ") {
      s[p2] = "0";
      s[--p2] = "2";
      s[--p2] = "%";
    } else {
      s[p2] = s[p1];
    }
    p1--;
    p2--;
  }
  return s.join("");
};

func replaceSpace(s string) string {
    return strings.Replace(s, " ", "%20", -1 )
}