Pset3 Tideman: Why is my sort_pairs function not working?

Question

I'm green on all the criteria before sort_pair. Here's my code so far:

// Sort pairs in decreasing order by strength of victory
void sort_pairs(void)
{
    // TODO
    // Create array of strengths of victory
    int strengths[pair_count];
    for (int i = 0; i < pair_count; i++)
    {
        strengths[i] = preferences[pairs[i].winner][pairs[i].loser];
    }

    // Bubble sort
    int swaps = 1;
    while (swaps > 0)
    {
        swaps = 1;
        for (int i = 0; i < pair_count - 1; i++)
        {
            if (strengths[i] < strengths[i + 1])
            {
                pair temp = pairs[i];
                pairs[i] = pairs[i + 1];
                pairs[i + 1] = temp;
                swaps++;
            }
        }
        swaps = swaps - 1;
    }
}

The code compiles but it doesn't pass check50. I'm not sure what's wrong with this. Could I please get some advice?

Answer 1

I managed to sort this out! The reason why this didn't work was because the program kept looping indefinitely at this line:

if (strengths[i] < strengths[i + 1])

When swapping the pairs, the program didn't swap elements in the "strengths" array, causing the loop to proceed indefinitely. I fixed the problem by making the program sort "strengths" as well:

        if (strengths[i] < strengths[i + 1])
        {
            // Swap strengths
            int tmpstrength = strengths[i];
            strengths[i] = strengths[i + 1];
            strengths[i + 1] = tmpstrength;

            // Swap pairs
            pair temp = pairs[i];
            pairs[i] = pairs[i + 1];
            pairs[i + 1] = temp;
            swaps++;
        }