search benchmarks

[kohl5555]

book question:
Write a program that has an array of at least 20 integers in a array in ascending order. It should call a function that uses the linear search algorithm to locate one of the values. The function should keep a count of the number of comparisons it makes until it finds the value. The program then should call a function that uses the binary search algorithm to locate the same value. It should also keep count of the number of comparisons it makes. Display these values on the screen.

my problem is:
i think i pretty much got what the book asked, only problem is teacher wants the user to be able to enter as many numbers as he or she wants. max of 20 obviously. which i'm not sure how to add.

  // C.I.S.P. 1010
// Lab:9 searching benchmarks 
// 4/15/17
#include <iostream>
using namespace std;

int searchList(const int[], int, int);
int binarySearch(const int[], int, int);

int main()
{
	int const SIZE = 20;
	int access[SIZE] = { 1, 5, 10, 13, 17, 24, 28, 33, 44, 49, 56, 61, 66, 78, 82, 85, 90, 94, 99, 100 };
	int resultSearch;
	int resultsBinary;
	int values;
	
	cout << "Please enter a valid value between 1 and 100: ";
	cin >> values;
	
	cout << "I will search for the value using searchList function\n";
	resultSearch = searchList(access, SIZE, values);
	
	if (resultSearch == -1)
		cout << "You did not enter a valid value.\n";
	
	else
	{
		cout << "You entered a valid value\n";
		cout << (resultSearch + 1) << "\n";
	}
	
	cout << "I will now search for the value using the Binary seach function.\n";
	resultsBinary = binarySearch(access, SIZE, values);

	if (resultsBinary == -1)
		cout << "You have entered an invalid value.\n";
	
	else
	{
		cout << "You have entered a valid value.\n";
		cout << resultsBinary << endl;
	}
	return 0;
}

int searchList(const int list[], int size, int value)
{
	int index = 0;
	
	while (index < size)
	{
		if (list[index] == value)
			return index;
		
		index++;

		}
	
	return -1; // Indicates value not found
	}

 int binarySearch(const int list[], int size, int value)
{
	int first = 0,
		last = size - 1,
		middle,
		position = -1;
	
	bool found = false;
	
	while (!found && first <= last)
	{
		middle = (first + last) / 2;
		
		if (list[middle] == value)
		{
			found = true;
			position = middle;
		}
		
		else if (list[middle] > value)
			last = middle - 1;
		else
			first = middle + 1;
	}
	
	return position;
}

[Enoizat]

the user to be able to enter as many numbers as he or she wants

You need a loop.
Since you have the upper limit (20), a for-loop looks the best choice. Otherwise you can opt for something like this (just an example):

// book question:
// Write a program that has an array of at least 20 integers in a array
// in ascending order.
// It should call a function that uses the linear search algorithm to locate
// one of the values.
// The function should keep a count of the number of comparisons it makes
// until it finds the value.
// The program then should call a function that uses the binary search algorithm
// to locate the same value.
// It should also keep count of the number of comparisons it makes.
// Display these values on the screen.

// my problem is:
// i think i pretty much got what the book asked, only problem is teacher wants
// the user to be able to enter as many numbers as he or she wants.
// max of 20 obviously. which i'm not sure how to add.

// C.I.S.P. 1010
// Lab:9 searching benchmarks
// 4/15/17
#include <iostream>
using namespace std;

int searchList(const int[], int, int);
int binarySearch(const int[], int, int);

int main()
{
   int const SIZE = 20;
   int access[SIZE] = { 1, 5, 10, 13, 17, 24, 28, 33, 44, 49,
                        56, 61, 66, 78, 82, 85, 90, 94, 99, 100 };

   int values = 0, countcycles = 0;
   do {
      countcycles++;
      cout << "\nRequest n. " << countcycles << ". Requests left: "
           << 20-countcycles << '\n';
      cout << "Please enter a valid value between 1 and 100: ";
      cin >> values;

      if(values < 1 || 100 < values)
      {
         cout << '\n' << values << " is out of range. Try again.\n";
         values = 1;
         continue;
      }

      cout << "I will search for the value using searchList function\n";
      int resultSearch = searchList(access, SIZE, values);

      if (resultSearch == -1)
      {
         cout << "You did not enter a valid value.\n";
      }
      else
      {
         cout << "You entered a valid value\n";
         cout << (resultSearch + 1) << "\n";
      }

      cout << "I will now search for the value using the Binary seach "
              "function.\n";
      int resultsBinary = binarySearch(access, SIZE, values);

      if (resultsBinary == -1)
      {
         cout << "You have entered an invalid value.\n";
      }
      else
      {
         cout << "You have entered a valid value.\n";
         cout << resultsBinary << endl;
      }
      // When countcycles gets here, the request has already been fullfilled,
      // therefore we need to consider a lower boundary (i.e. 19 instead of 20).
   } while(0 < values && values < 101 && countcycles < 19);

      return 0;
}

int searchList(const int list[], int size, int value)
{
   int index = 0;

   while (index < size)
   {
      if (list[index] == value)
         return index;

      index++;
   }

   return -1; // Indicates value not found
}

int binarySearch(const int list[], int size, int value)
{
   int first = 0,
         last = size - 1,
         middle,
         position = -1;

   bool found = false;

   while (!found && first <= last)
   {
      middle = (first + last) / 2;

      if (list[middle] == value)
      {
         found = true;
         position = middle;
      }
      else if (list[middle] > value)
         last = middle - 1;
      else
         first = middle + 1;
   }

   return position;
}