chore(CPlusPlus): add search sorted rotated (#316)

algorithms/CPlusPlus/Arrays/search-sorted-rotated.cpp

@@ -0,0 +1,48 @@
+//Description : Searching element in a sorted-rotated array using binary search
+#include<bits/stdc++.h>
+using namespace std;
+int search_array(vector <int> arr, int item) {
+    int low = 0;
+    int high = arr.size() - 1;
+    while (low <= high) {
+        int mid = low + (high-low)/2;                            //Calculating middle index
+        if (arr[mid] == item) {                                 //If the element at middle index is equal to the item then we return the middle index
+            return mid;
+        } 
+        else if (arr[mid] > arr[low]) {                         //Here we check whether left half of the array is sorted or not .
+            if ((arr[low] <= item) && (item<arr[mid])) {        // If left half is sorted then we check whether item is greater than the lower index 
+                high = mid - 1;                                 //If  item is greater than the lower index then we ignore the right half of the array
+            }                     
+            else {                                             //If item is less than the lower index then we ignore the left half and start our search
+                low = mid + 1;                                 //in the right half of the array
+            }
+        } 
+        else {                                                 //This execute if right half is sorted
+            if ((arr[high] >= item) && (item>arr[mid])) {      //We check whether our item is smaller or equal to the upper index 
+                low = mid + 1;                                 //If yes, then we start our search within the range (mid+1,high)
+            } 
+            else {
+                high = mid - 1;                                //If item is greater than the element at higher index then we start
+            }                                                  //our search in the range(low,mid-1)
+        }
+    }
+    return -1;
+}
+int main() {
+    int t ;
+    int n;                       
+    int item;
+    vector <int> arr;
+    cin >> t;                                                 //Size of the array
+    while (t--) {
+        cin >> n;
+        arr.push_back(n);
+    }
+    cin >> item;
+    int found = search_array(arr, item);
+    cout << found << endl;
+    return 0;
+    //Time Complexity : O(log t)
+    //Ex:  t=5, arr=[10,20,30,40,50,8,9], item=30
+    //found = 2
+}

algorithms/CPlusPlus/README.md

@@ -8,6 +8,7 @@
 5. [Shift Negatives](Arrays/shift-negatives.cpp)
 6. [Boyer–Moore Voting Algorithm](Arrays/boyer_more.cpp)
 7. [Reverse Array](Arrays/reverse-array.cpp)
+8. [Sorted-Rotated Search Array](Arrays/search-sorted-rotated.cpp)
 
 ## Graphs
 1. [Bellman Ford Algorithm](Graphs/bellmam-ford.cpp)