helpers.c passes check50 but fails ./generate 1000 50 | ./find 128

Question

check50 gives me all smiles, but when I run the test code ./generate 1000 50 | ./find 127 or 128 they both return "Found needle in haystack". How is that possible? And also, can I be sure my code is right based on the results from check50 even though the debugging test they suggested themselves fails in one of the scenarios? Please help me.

Here is my basic implementation for bool search(int value, int values[], int n), considering that min is 0, max is n - 1, and middle is min + max / 2:

//pseudo code
    for loop int i is 0; i less than n; i++ 
    {
        if max less than min just return 1; 

        else
            if values[i] less than value
                min is middle + 1; 

            else if values[i] greater than value    
                max is middle - 1; 

            else
                just return middle; 
    }
    return 0;

And here is my basic implementation of void sort(int values[], int n):

for loop int i is 0; i less than n; i++
{
    for loop int j is i; j less than *values; j++
    {
        if values[j] less than values[i]
        {
            swapper is values[j];
            values[j] is values[i];
            values[i] is swapper;
        }
    }
}

Answer 1

Looking at your pseudocode gives me some thoughts, but also reduces confidence on how accurate my analysis is. I'd prefer to see actual code. Not sure if your sort works because I'm unsure what the for loop limit on j really is. However, I'm pretty sure that you have some serious issues with your search function.

It is always dangerous to return numbers when a function calls for the return of a bool. Instead, it's always best to return true or false when returning a bool. When numbers are returned, a 0 is always interpreted as false, and a non-zero is interpreted as true. The first return should be a false, but it returns 1. I'm not entirely sure what you wish to return in later statements. This could account for why your test is returning the results you see.

Note that there's also a common practice of returning 0 when a program or function completes, or a non-zero to indicate a specific error. This is directly opposite from how numbers are interpreted when a bool is supposed to be returned. Don't confuse the two standards.

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