Bubble sort all but first spot

Question

If I change the condition (i < n -1) to (i < n) it glitches, and as it is now, all but the first position [0] gets sorted.

int sortIndexByDate(Match match[], int n)
{
    int i, j, sum[n], swapped;
    for (i = 0; i < n; i++)
        sum[i] = match[i].d.year*10000 + match[i].d.month*100 + match[i].d.day;
    do {
        swapped = false;
        for (i = 1; i < n - 1; i++) {
            if (sum[i] < sum[i + 1]) {
                swapInt(&sum[i], &sum[i+1]);
                swapMatch(&match[i], &match[i+1]);
                swapped = true;
            }
        }
        n--;
    } while (swapped);
}

Hmm... `i < n -1`... That defines the **end** of the range... but the error is at the **beginning** of the range... So if you were to change the beginning of the range... ? — beaker, Oct 12 '14 at 02:18

score 0 · Accepted Answer · answered Oct 12 '14 at 02:19

0

You are starting at i = 1 in inner loop. Hence sum[0] is being ignored.

Change it to

for (i = 0; i < n-1; i++) {

answered Oct 12 '14 at 02:19

Buddha

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The `i < n - 1` is correct, since he's accessing `sum[i]` and `sum[i + 1]` – Dmitri Oct 12 '14 at 02:20
@Dmitri Thanks, I missed it – Buddha Oct 12 '14 at 02:21

Bubble sort all but first spot

1 Answers1