#include <stdio.h> 
int binarySearch(int arr[], int size, int target) { 
int left = 0; 
int right = size - 1; 
while (left <= right) { 
int mid = left + (right - left) / 2; 
 
 
if (arr[mid] == target) { 
return mid; 
} 
if (arr[mid] < target) { 
left = mid + 1; 
} else { 
right = mid - 1; 
 
} 
} 
 
return -1; 
} 
 
int isSorted(int arr[], int size) { 
for (int i = 1; i < size; i++) { 
if (arr[i] < arr[i - 1]) { 
return 0; 
} 
} 
 
return 1; 
} 
 
int main() { 
  
int size, key; 
printf("Enter the number of elements: "); 
scanf("%d", &size); 
int arr[size]; 
printf("Enter the elements in sorted order:\n"); 
for (int i = 0; i < size; i++) { 
scanf("%d", &arr[i]); 
 
} 
if (!isSorted(arr, size)) { 
printf("The elements are not entered in sorted order.\n"); 
return 0; 
} 
printf("Enter the element to search for: "); 
scanf("%d", &key); 
int result = binarySearch(arr, size, key); 
if (result != -1) { 
printf("Element found at index: %d\n", result); 
} else { 
printf("Element not found in the array.\n"); 
 
} 
return 0; 
}