https://leetcode.com/problems/reverse-integer/
Given a signed 32-bit integer x
, return x
 with its digits reversed. If reversing x
 causes the value to go outside the signed 32-bit integer range [-231, 231 - 1]
, then return 0
.
Assume the environment does not allow you to store 64-bit integers (signed or unsigned).
Example 1:
Input: x = 123 Output: 321
Example 2:
Input: x = -123 Output: -321
Example 3:
Input: x = 120 Output: 21
Constraints:
-231Â <= x <= 231Â - 1
const reverse = (x: number) => {
 const absoluteNumber = Math.abs(x);
 const isNegative = x <= 0;
 let y = absoluteNumber.toString();
 if (y.length > 10 || (y.length === 10 && Number(y[y.length - 1]) >= 3))
  return 0;
 let reversed = Number(y.split("").reverse().join(""));
 return reversed > 2147483647 || reversed < -2147483648
  ? 0
  : isNegative
  ? -reversed
  : reversed;
};
console.log(reverse(1234567893));
Submission Detail
1032 / 1032Â test cases passed. | Status:Â Accepted |
Runtime:Â 70 ms Memory Usage:Â 45.2 MB | Submitted:Â 3Â months ago |
https://leetcode.com/problems/reverse-words-in-a-string/
Given an input string s
, reverse the order of the words.
A word is defined as a sequence of non-space characters. The words in s
 will be separated by at least one space.
Return a string of the words in reverse order concatenated by a single space.
Note that s
 may contain leading or trailing spaces or multiple spaces between two words. The returned string should only have a single space separating the words. Do not include any extra spaces.
Example 1:
Input: s = "the sky is blue" Output: "blue is sky the"
Example 2:
Input: s = " hello world " Output: "world hello" Explanation: Your reversed string should not contain leading or trailing spaces.
Example 3:
Input: s = "a good example" Output: "example good a" Explanation: You need to reduce multiple spaces between two words to a single space in the reversed string.
Constraints:
1 <= s.length <= 104
s
 contains English letters (upper-case and lower-case), digits, and spacesÂ' '
.- There is at least one word inÂ
s
.
Follow-up: If the string data type is mutable in your language, can you solve it in-place with O(1)
 extra space?
let s = "the  sky is blue";
function reverseWords(s: string): string {
 let currentWord = "";
 let result = "";
 for (let i = 0; i < s.length; i++) {
  const char = s[i];
  if (char !== " ") {
   currentWord += char;
  }
  if (currentWord.length > 0 && (char === " " || i === s.length - 1)) {
   result = result === "" ? currentWord + result : currentWord + " " + result;
   currentWord = "";
  }
 }
 return result;
}
console.log(reverseWords(s));
Submission Detail
58 / 58Â test cases passed. | Status:Â Accepted |
Runtime:Â 113 ms Memory Usage:Â 44.9 MB | Submitted:Â 3Â months ago |
https://leetcode.com/problems/length-of-last-word/
Given a string s
 consisting of words and spaces, return the length of the last word in the string.
A word is a maximal substring consisting of non-space characters only.
Â
Example 1:
Input: s = "Hello World" Output: 5 Explanation: The last word is "World" with length 5.
Example 2:
Input: s = " fly me to the moon " Output: 4 Explanation: The last word is "moon" with length 4.
Example 3:
Input: s = "luffy is still joyboy" Output: 6 Explanation: The last word is "joyboy" with length 6.
Â
Constraints:
1 <= s.length <= 104
s
 consists of only English letters and spacesÂ' '
.- There will be at least one word inÂ
s
.
function lengthOfLastWord(s: string) {
 let finalCount = 0;
 let k = s.length - 1;
 if (s[k] === " ") {
  k--;
  while (s[k] === " ") {
   k--;
  }
 }
 for (let i = k; i >= 0; i--) {
  if (s[i] !== " ") finalCount++;
  else return finalCount;
 }
 return finalCount;
}
Submission Detail
58 / 58Â test cases passed. | Status:Â Accepted |
Runtime:Â 53 ms Memory Usage:Â 43.4 MB | Submitted:Â 3Â months ago |