Adding 704-Binary-Search.c

Author: FahadulShadhin

c/704-Binary-Search.c

@@ -0,0 +1,30 @@
+/*
+    Given an array of integers, search for a target value.
+    Examples: 
+        nums = [-1,0,3,5,9,12], target = 9, return 4 (index of target 9)
+        nums = [-1,0,3,5,9,12], target = 2, return -1 (not found)
+    Array is sorted, so perform binary search
+
+    Time: O(log n)
+    Space: O(1)
+*/
+
+int search(int* nums, int numsSize, int target) {
+    int left = 0;
+    int right = numsSize-1;
+    
+    while (left <= right) {
+        int mid = left + (right - left) / 2;
+
+        if (nums[mid] == target) {
+            return mid;
+        } 
+        else if (nums[mid] < target) {
+            left = mid + 1;
+        }
+        else {
+            right = mid - 1;
+        }
+    }
+    return -1;
+}