solves smallest letter greater than

Author: anishLearnsToCode

Diff for: python/find_smallest_letter_greater_than.py

@@ -0,0 +1,11 @@
+from typing import List
+
+
+class Solution:
+    def nextGreatestLetter(self, letters: List[str], target: str) -> str:
+        left, right = 0, len(letters) - 1
+        while left <= right:
+            middle = left + (right - left) // 2
+            if letters[middle] <= target: left = middle + 1
+            else: right = middle - 1
+        return letters[left % len(letters)]

Diff for: src/FindSmallestLetterGreaterThanTarget.java

@@ -0,0 +1,11 @@
+public class FindSmallestLetterGreaterThanTarget {
+    public char nextGreatestLetter(char[] letters, char target) {
+        int left = 0, right = letters.length - 1, middle;
+        while (left <= right) {
+            middle = left + (right - left) / 2;
+            if (letters[middle] <= target) left = middle + 1;
+            else right = middle - 1;
+        }
+        return letters[left % letters.length];
+    }
+}