CS50 Helpers.C Find Less, No Idea What's Going On

Question

Final Code:

/**
 * helpers.c
 *
 * Helper functions for Problem Set 3.
 */

#include <cs50.h>

#include "helpers.h"

/**
 * Returns true if value is in array of n values, else false.
 */
bool search(int value, int values[], int n)
{
    // TODO: implement a searching algorithm
    if (n <= 0)
    {
        return false;
    }
    int min = 0; 
    int max = n - 1;

    while (n > 0)
    {
        int mid = (max - min) / 2 + min;

        if (value == values[mid])
        {
            return true;

        }
        else if (value > values[mid])
        {
            min = mid + 1;
        }

        else if (value < values[mid])
        {
            max  = mid - 1;
        }

        n = max - min + 1;


    }

    return false;  




} 


/**
 * Sorts array of n values.
 */
void sort(int values[], int n)
{
    int swap;
    for (int i = 0; i < n-1; i++)
    {
        for (int j = 0; j < n - i - 1; j++)
        {
            if (values[j] >  values[j + 1])
            {
                swap = values[j];
                values[j] = values[j + 1];
                values[j + 1] = swap;
            }

        }
    }
    return;
}

Answer 1

Both search and sort have problems. First, sort isn't complete. It only makes one pass through the list, so it will only bubble sort the largest value to the last position. I suggest a review of the lectures and class material on bubble sorts.

Second (and without doing an in-depth analysis), it looks like the search routine goes into an infinite loop when the target is not in the list. Note that all of the later tests that fail are cases where the target is not in the list.

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