pset3 - Binary search not finding the element in middle

Question

Binary search doesn't seem to find the element in middle.

int binary_search(int value, int values[], int n) {
    int low = 0;
    int high = n-1;
    while( high >= low )
    {
        int mid = (high + low) / 2;

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

        if ( values[mid] > value ) {
            high = mid -1;
        } else if ( values[mid] < value ) {
            low = mid +1;
        }
    }
    return -1;
}

:( finds 42 in {41,42,43} \ expected an exit code of 0, not 1

link to check50

Answer 1

In testing, the code works fine. Is it possible that you have a problem with your sort function? Have you verified that sort is correct by printing out the sorted list with different test data?

As a side note, I am curious why you decided to write binary_search() the way you did. Specifically, search returns a bool, while binary_search returns an int. Your binary_search could easily just return a bool instead of an int by replacing the return type and returning true or false instead of a number. In short, it could have been directly written as search() instead of calling another function from search(). Yes, it works, but why introduce an additional function when you don't have to?

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