Added one solution & refactored one solution

varunu28 · varunu28 · commit 5b428bd89a01 · 2019-12-26T06:45:47.000+05:30
diff --git a/Easy/Binary Search.java b/Easy/Binary Search.java
@@ -1,23 +1,21 @@
 class Solution {
-    public int search(int[] nums, int target) {
-        return searchImpl(nums, target, 0, nums.length-1);
-    }
-    
-    public int searchImpl(int[] nums, int target, int start, int end) {
-        if (start > end) {
-            return -1;
-        }
-        
-        int mid = (start + end)/2;
-        
-        if (nums[mid] == target) {
-            return mid;
-        }
-        else if (nums[mid] > target) {
-            return searchImpl(nums, target, start, mid-1);
-        }
-        else {
-            return searchImpl(nums, target, mid+1, end);
-        }
+  public int search(int[] nums, int target) {
+    return binarySearchImpl(nums, 0, nums.length - 1, target);
+  }
+  
+  private int binarySearchImpl(int[] nums, int start, int end, int target) {
+    while (start <= end) {
+      int mid = (start + end) / 2;
+      if (nums[mid] == target) {
+        return mid;
+      }
+      else if (nums[mid] > target) {
+        end = mid - 1;
+      }
+      else {
+        start = mid + 1;
+      }
     }
+    return -1;
+  }
 }
diff --git a/Easy/Find Smallest Letter Greater Than Target.java b/Easy/Find Smallest Letter Greater Than Target.java
@@ -0,0 +1,24 @@
+class Solution {
+  public char nextGreatestLetter(char[] letters, char target) {
+    int start = 0;
+    int end = letters.length - 1;
+    // ASCII char greater than 'z'
+    char smallestChar = '{';
+    while (start <= end) {
+      int mid = (start + end) / 2;
+      if (letters[mid] - target > 0) {
+        if (smallestChar - letters[mid] > 0) {
+          smallestChar = letters[mid];
+        }
+        end = mid - 1;
+      }
+      else if (letters[mid] - target == 0) {
+        start = mid + 1;
+      }
+      else {
+        start = mid + 1;
+      }
+    }
+    return smallestChar == '{' ? letters[0] : smallestChar;
+  }
+}
