Added BinarySearch

BinarySearch.cpp

@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int search(vector<int>& nums, int target) {
+        int n = nums.size(); //size of the array
+    int low = 0, high = n - 1;
+
+    // Perform the steps:
+    while (low <= high) {
+        int mid = (low + high) / 2;
+        if (nums[mid] == target) return mid;
+        else if (target > nums[mid]) low = mid + 1;
+        else high = mid - 1;
+    }
+    return -1;
+    }
+};