easy binary search program in cpp

Given an array of integers nums which is sorted in ascending order, and an integer target, write a function to search target in nums. If target exists, then return its index. Otherwise, return -1.

You must write an algorithm with O(log n) runtime complexity.

 

Example 1:

Input: nums = [-1,0,3,5,9,12], target = 9
Output: 4
Explanation: 9 exists in nums and its index is 4
Example 2:

Input: nums = [-1,0,3,5,9,12], target = 2
Output: -1
Explanation: 2 does not exist in nums so return -1

Author: Gauranshgoel123

binary-search.cpp

@@ -0,0 +1,21 @@
+class Solution {
+public:
+    int search(vector<int>& nums, int target) {
+        int beg=0;
+        int n=nums.size();
+        int end=n-1;
+        while(beg<=end){
+            int mid=(beg+end)/2;
+            if (nums[mid]==target){
+                return mid;
+            }
+            else if(nums[mid]>target){
+                end=mid-1;
+            }
+            else if(nums[mid]<target){
+                beg=mid+1;
+            }
+        }
+        return -1;        
+    }
+};