#include <iostream>
#include <bits/stdc++.h>
using namespace std;

class solution{ 
  int findPeak(int arr[], int n){
    int first = 0, last = n-1, mid=0, res=-1;
    while(first<=last){
      mid = first + (last-first)/2;
      if(mid>0 && mid<n-1){
        if(arr[mid]>arr[mid-1] && arr[mid]>arr[mid+1]) 
        return mid;
        else if(arr[mid-1]<arr[mid]) first = mid + 1;
        else last = mid - 1;
      }
      else if(mid == 0){
        if(arr[mid]>arr[mid+1]) return mid;
      } 
      else{
        if(arr[mid]>arr[mid-1]) return mid;
      }
    }
    return res;
  }
  
  int binarySearch(int arr[], int first, int last, int k, int flag){
    while(first<=last){
      int mid = first + (last - first)/2;
      if(arr[mid] == k){
        return mid;
      }
      else if(k<arr[mid] && flag == 0){
        last = mid - 1;
      }
      else if(k>arr[mid] && flag == 0){
        first = mid + 1;
      }
      else if(k<arr[mid] && flag == 1){
        first = mid + 1;
      }
      else{
        last = mid - 1;
      }
    }
    return -1;
  }
  
  public:
  int maxElement(int arr[], int n, int k){
    int peak = findPeak(arr, n);
    int res = -1;
    int flag = 0;//for left ascending side in bitonic array
    res = binarySearch(arr, 0, peak - 1, k, flag);
    if(res != -1)return res;
    flag = 1;//for right decending side in bitonic array
    res = binarySearch(arr, peak, n-1, k, flag);
    return res;
  }
};

int main() 
{
  int n,k;
  cin>>n;
  int arr[n];
  for(int i=0; i<n; i++){
    cin>>arr[i];
  }
  cin>>k;
  solution ob;
  int res = ob.maxElement(arr,n, k);
  cout<<res;
  return 0;
}
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Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}