Today I have done leetcode's June LeetCoding Challenge with cpp.

June LeetCoding Challenge 9

Description

Find Smallest Letter Greater Than Target

You are given an array of characters letters that is sorted in non-decreasing order, and a character target. There are at least two different characters in letters.

Return the smallest character in letters that is lexicographically greater than target. If such a character does not exist, return the first character in letters.

Example 1:

Input: letters = ["c","f","j"], target = "a"
Output: "c"
Explanation: The smallest character that is lexicographically greater than 'a' in letters is 'c'.

Example 2:

Input: letters = ["c","f","j"], target = "c"
Output: "f"
Explanation: The smallest character that is lexicographically greater than 'c' in letters is 'f'.

Example 3:

Input: letters = ["x","x","y","y"], target = "z"
Output: "x"
Explanation: There are no characters in letters that is lexicographically greater than 'z' so we return letters[0].

Constraints:

• 2 <= letters.length <= 104
• letters[i] is a lowercase English letter.
• letters is sorted in non-decreasing order.
• letters contains at least two different characters.
• target is a lowercase English letter.

Solution

class Solution {
public:
  char nextGreatestLetter(vector<char>& letters, char target) {
    for(auto letter : letters) {
      if(letter > target) return letter;
    }
    return letters[0];
  }
};

// Accepted
// 167/167 cases passed (15 ms)
// Your runtime beats 75.46 % of cpp submissions
// Your memory usage beats 96.78 % of cpp submissions (15.8 MB)