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Recursive Binary Search Algorithm C++

#include<iostream>

bool is_in_array(int* begin, int* end, int target){

  int mid = (end - begin)/2;
  
  if(*begin>target || *end<target) //value has to be between [begin,end] 
    return false;                  // to continue
  
  if(begin[mid] == target)        
    return true;

  if(begin[mid] > target)     //look at the left subarray
     return is_in_array(begin,begin+mid-1,target);
  
  // (begin[mid] < target) look at the right subarray
  return is_in_array(begin+mid+1,end,target);
}

bool find_in_array(int arr[] ,int target,int size){
 
    int* begin = arr;
    int* end = begin+size-1;
    bool result = is_in_array(begin,end,target);   
    return result;
}

void test_is_in_array(bool expected, int arr[],int target,int size){

  bool result = find_in_array(arr,target,size);
  std::cout<<(result==expected?"PASS: ":"FAIL: ")
           <<" result => "<<result<<" expected =>"
           <<expected<<std::endl;

}

int main( void ){

  int arr1[] = {1,3,5,7,9,10};
  int arr2[] = {1,3,7,9,10};
  int arr3[] = {1,3,5,7,9,10,11,15,16,16,16,16,16,19,20};
  int arr4[] = {1,3,5,7,9,10,15,20,25,50,1000,1000001};
  int arr5[] = {1,3,5,7,9,10,11,12,13,14};
  
  test_is_in_array(0,arr1,0,sizeof(arr1)/sizeof(*arr1));
  test_is_in_array(1,arr2,7,sizeof(arr2)/sizeof(*arr2));
  test_is_in_array(1,arr3,16,sizeof(arr3)/sizeof(*arr3));
  test_is_in_array(1,arr4,50,sizeof(arr4)/sizeof(*arr4));
  test_is_in_array(0,arr5,15,sizeof(arr5)/sizeof(*arr5));
  test_is_in_array(1,arr5,14,sizeof(arr5)/sizeof(*arr5));

  
  
  return 0;
}

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