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  1. #include <stdio.h>
  2. #include <iostream>
  3. #include <iomanip>
  4.  
  5. using namespace std;
  6.  
  7. int binarySearch(const int [], int, int, int, int ); // function prototype
  8.  
  9. int main()
  10. {
  11.     const int arraySize = 10;
  12.     int arr[ arraySize ];
  13.     int key;
  14.  
  15.     for( int i = 0; i < arraySize; i++)  // generate data for array
  16.        arr[i] = 2*i;
  17.  
  18.     cout << "The array being searched is: " << endl;
  19.  
  20.     for (int j = 0; j<arraySize; j++)  // print subscript index of the array
  21.     {
  22.     cout << setw(5) << j << " ";
  23.     }
  24.  
  25.     cout << endl;
  26.  
  27.     for (int z = 0; z<arraySize; z++) // print elements of the array below     index
  28.     {
  29.      cout << setw(5) << arr[z] << " ";
  30.     }
  31.  
  32.     cout << "\n" <<"Enter value you want to search in array " << endl;
  33.     cin >> key;
  34.  
  35.     int result = binarySearch(arr, key, 0, arraySize, arraySize); // function call
  36.  
  37.     if (result == 1)                  // print result of search
  38.     cout << "Key is found " << endl;
  39.     else
  40.     cout << "Key not found " << endl;
  41.  
  42.     return 0;
  43. } // end main function
  44.  
  45. int binarySearch(const int a[], int searchKey, int low, int high, int length)
  46. {
  47.     int middle;
  48.  
  49.     while (low <= high){
  50.  
  51.     middle = (low + high) / 2;
  52.  
  53.     if (searchKey == a[middle]) // search value found in the array, we have a match
  54.     {
  55.         return 1;
  56.         break;
  57.     }
  58.  
  59.     else
  60.     {
  61.         if( searchKey < a[middle] )  // if search value less than middle element
  62.             high = middle - 1;      // set a new high element
  63.         else
  64.             low = middle + 1;       // otherwise search high end of the array
  65.     }
  66.     }
  67. return -1;
  68. }
Success #stdin #stdout 0s 3464KB
comments (?)
stdin 
21
stdout 
The array being searched is: 
    0     1     2     3     4     5     6     7     8     9 
    0     2     4     6     8    10    12    14    16    18 
Enter value you want to search in array 
Key not found
https://ideone.com/aIYbZN
language:
C++ (gcc 8.3)
created:
8 years ago
visibility:
secret

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