快速排序

void quick_sort(int q[], int l, int r)//l为数组起始坐标，r为数组终止坐标
{
    if (l >= r)
        return;
    int x = q[l], i = l - 1, j = r + 1;
    while(i < j)
    {
        do
            i++;
        while (q[i] < x);
        do
            j--;
        while (q[j] > x);
        if(i < j)
            swap(q[i], q[j]);
    }
    quick_sort(q, l, j);//递归处理前段   注意边界问题
    quick_sort(q, j + 1, r);//递归处理后段
}

归并排序

void merge_sort(int q[], int l, int r)//l为数组起始坐标，r为数组终止坐标
{
    if(l >= r)
        return;
    int mid = (r + l) >> 1;
    merge_sort(q, l, mid);//递归排序左边
    merge_sort(q, mid + 1, r);//递归排序右边
    int k = 0, i = l, j = mid + 1;
    while(i <= mid && j <= r)
        if(q[i] <= q[j])
            temp[k++] = q[i++];
        else
            temp[k++] = q[j++];
    while(i <= mid)             //处理剩余项
        temp[k++] = q[i++];
    while (j <= r)
        temp[k++] = q[j++];
    for (int i = l, j = 0; i <= r; i++, j++)
        q[i] = temp[j];
}