PSET3 - Find (More) - Debugging and bubble sort issues

Question

Pset 3 (2017): create program, find, that finds a number in an array of generated numbers. We need to implement functions for both sorting and searching the array using helper files. Since a binary search is being used we have to sort the array first in numerical order before we can search.

I feel like I have correctly implemented the bubble sort, as when I ran the sort function in a separate file of it's own it properly sorted through an array an ordered it.

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However when I try to execute using the PSET guidelines and the same sort function I run into some problems, leading me to believe the sort isn't working right.

For easier testing, I have a nums.txt file that contains {25, 20, 15, 10, 5, 2, 1}.

./find 2 < nums.txt gives me "Didn't find needle in haystack"

./find 25 < nums.txt gives me "Found needle in haystack"

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debug50 ./find 2 < nums.txt and trying to debug doesn't work for me either, so I can't get to one step my code.

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Does anybody have any insight on how I can get the right output when using ./find or even how I can fix debugging to get a clearer idea of the problem? Here is the helper.c file.

#include <cs50.h>
#include "helpers.h"

bool search(int value, int values[], int n)
    {
    // is array filled?
    if (n <= 0)
    {
        return false;
    }
    
    int start = 0;
    int end = n - 1;
    int mid = (start + end) / 2;
    
    // iterate through each value within array 
    while (start <= end)
    {
        if (values[mid] == value)
        {
            return true;
        }
                
        if (values[mid] << value)
        {
            start = mid + 1;
            mid = (start + end) / 2;
        }
        
        else if (values[mid] >> value)
        {
            end = mid - 1;
            mid = (start + end) / 2;
        }
    }
    return false;
}




void sort(int values[], int n)
{
    int temp;
    int i, j;
    int swapcount = 0;
    
    for (i = 0; i < n - 1; i++)
    {
        for (j = 0; j < n - 1 - i; j++)
        {
            if (values[j] > values[j+1])
            {
                temp  = values[j];
                values[j] = values[j+1];
                values[j+1] = temp;
                swapcount = swapcount + 1;
            }
        }
    
        if (swapcount == 0)
        {
            break;
        }
    }
}

Answer 1

    if (values[mid] << value)
    ...
    else if (values[mid] >> value)

What are the operators >> and << and what are the operators > and <???

Of course, this is no longer part of the class, but good exercise to finish it. ;-)

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