Arrays, Binary Seaching and Selection sorting.

Jp P (18)
Hi i'm up at 4am trying to figure out why my code won't work right. It compiles with no errors, but i'm not getting what i want. It's just a program that reads from a file and stores the 40 values in an array, sorts them with selection, then uses a binary search to find a value. Here she is:

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#include<iostream>
#include<string>
#include<fstream>
#include<cstring>
#include <cstdlib>
#include<iomanip>
using namespace std;

void selectionSort(int [], int);
int binarySearch(int [], int , int);
const int SIZE = 40;
 


int main()
{
	
	int array [SIZE];
	int count = 0; 

	
	ifstream inputFile;
	string filename;
	int value, result;
	int median;
	


	cout << "Enter the filename: ";
	cin >> filename;

	inputFile.open (filename.c_str());

	cout<<"-----------------------------------------"<<endl;
	 
	if (inputFile)
	{
		
		while(count < SIZE && inputFile >> array[count])
			count++;

		cout << "There are "<< count <<" many values: "<<endl;

			
		for(int i = 0; i < count; i++)
		{
			cout << array[i] << endl;
			
		}
	}
	
	


	else 
	{
		while(!(inputFile))
		{
			cout << "Error opening file " <<filename<<endl;
			cout << "Re-enter the filename: ";
			cin >> filename;

			inputFile.open (filename.c_str());
		}
	
		while(count < SIZE && inputFile >> array[count])
			count++;
			
		for(int i = 0; i < count; i++)
			cout << array[i] << endl;		
	

	}


		
	inputFile.close();

	cout<<" "<<endl;
	cout<<"There are "<< count<< " numbers in " << filename<<endl;
	cout<<"-----------------------------------------"<<endl;
	selectionSort(array, SIZE);
	
	for(int q = 0; q < count; q++)
	{
			cout << array[q] << endl;
			
	}




	median = SIZE/2;
	cout<<"-----------------------------------------"<<endl;
	cout<<"The Median of the data set is: "<< array[median] << endl;
	cout<<"-----------------------------------------"<<endl;
	cout<<"Enter the number you're looking for: ";
	cin >> value;
	result = binarySearch(array, SIZE, value);
	if(result == -1)
	{
		cout<<"That number doesn't exist in the array."<<endl;
		return 0;
	}
	else 
	{
		cout<<"That number is found at element " << result;
		cout<< " in the array."<<endl;
	}




	
	
	

return 0;

}



void selectionSort(int a[], int size)
{

      int i, j, minIndex;
      int tmp;    



      for (i = 0; i < size - 1; i++) 
      {
		minIndex = i;

        for (j = i + 1; j < size; j++)
           if (a[j] < a[minIndex])
                 minIndex = j;

            if (minIndex != i) 
            {
            	tmp = a[i];
				a[i] = a[minIndex];
				a[minIndex] = tmp;

            }

      }

}

int binarySearch(int a[],int size,int target)
{
	int first =0,
		last = size -1,
		middle,
		position = -1;
	bool found = false;

	while(!found && first<=last)
	{
		middle = (first <= last) /2;
		if(a[middle] == target)
		{
			found = true;
			position = middle;
		}
		else if(a[middle] > target)
			last = middle -1;
		else if(a[middle] < target)
			first = middle +1;
	}
	return position;
	}


please i want to go to bed..
Gaminic (1621)
"i'm not getting what I want" -> could you be more specific? Is it not sorting, or is the output bogus, or what?
Jp P (18)
That's the thing i can't show you the output because there isn't one. I'm sorry i should include that yes it does sort, and outputs the array, then the array in the order, the problem is somewhere in between 98-107. When i type in a number to search i press enter and nothing happens :3 did i do something wrong with cin>> or result?
Gaminic (1621)
Line 162: middle = (first <= last) /2;

Not sure what that's supposed to be. (first <= last) returns a boolean which, when divided by two, becomes 0.
Should probably be (first+last)/2.
Jp P (18)
Gaminic i don't know how i can repay you, thank you so much for being up this late/early you are my hero.
Gaminic (1621)
You're very welcome.
(Also, it's around noon here, so don't worry about it!)
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