三种排序C语言（冒泡、选择、快排）

for (int i = 1; i < n; i++)
{
    for (int j = 0; j < n - i; j++)
    {
        if (a[j] > a[j - 1])
        {
            int temp = a[j];
            a[j] = a[j + 1];
            a[j + 1] = t;
        }
    }
}

for (int i = 0; i < n - 1; i++)
{
    int t = i;
    for (int j = i + 1; j < n; j++)
    {
        if (a[t] > a[j])
        {
            t = j;
        }
    }
    if (t != i)
    {
        int temp = a[i];
        a[i] = a[t];
        a[t] = temp;
    }
}
qsort(a, k, sizeof(a[0]), cmp);

整形数组排序

static int cmp(const void *a, const void *b)
{
    return *(int *)a - *(int *)b;
}
qsort(a, k, sizeof(a[0]),cmp); // a为数组，k为数组长度

字符数组排序

static int cmp(const void *a, const void *b)
{
    return *(char *)a - *(char *)b;
}
qsort(a, len, sizeof(a[0]), cmp);

字符串排序

char a[][10] = {"asasd","asdsfd","sd"};
static int cmp(const void *a,const void *b)
{
    return strcmp((char *)a, (char *)b);
}
qsort(a, k, sizeof(a[0]),cmp); // k = 3;

二维数组排序

char a[][2]={1,2,3,4,2,3,4,5};
static int cmp(const void *a, const void *b)
{
    int *x = *(int **)a;
    int *y = *(int **)b;
    if (x[0] == y[0])
    {
        return x[1] - y[1];
    }
    return x[0] - y[0];
}
qsort(a, k, sizeof(a[0]), cmp); // k = 4