Hello,
This mailing list is for the development of GCC, not for using it.
gcc-help might be more appropriate for this kind of question, although
it doesn't seem to be GCC related.
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On Fri, 2013-08-02 at 18:25 -0700, eric lin wrote:
>
> I have tried to copy QuickSort c++ programs:
> -----------------------------------------------
> #include <iostream>
> using namespace std;
>
>
> class Element
> {
> public:
> int getKey() const { return key;};
> void setKey(int k) { key=k;};
> private:
> int key;
> // other fields
>
> };
>
> #define InterChange(list, i, j) t=list[j]; list[i]=list[j]; list[j]=t;
This is probably wrong. In your code it expands to
if (i < j)
t = list[j];
list[i] = list[j];
list[j] = t;
Make InterChange a function instead of a macro and try again.
> /*-------------------------------------------------------------------------------------*/
>
>
> void QuickSort(Element list[], /* const */ int left, /*const */ int right)
> // Sort records list[left], ..., list[right] into nondescreasing order on field key.
> // Key pivot = list[left].key is arbitrarily chosen as the pivot key. Pointer i and j
> // are used to partition the sublist so that at any time list[m].key <= pivot, m < i;
> // and list[m].key >= pivot, m>j. It is assumed that list[left].key <=list[right+1].key.
> {
> Element t;
>
> if (left<right) {
> int i = left,
> j=right+1,
> pivot=list[left].getKey();
> do {
> do i++; while(list[i].getKey() < pivot);
> do j--; while(list[j].getKey() > pivot);
> if (i<j) InterChange(list, i, j);
> } while(i<j);
> InterChange(list, left, j);
>
> cout << "---show bankaccount1[0]= " << list[0].getKey() << " bankaccount1[1]= " << list[1].getKey() << " bankaccount1[7]= " << list[7].getKey() << " its left= " << left << endl;
> QuickSort(list, left, j-1);
> QuickSort(list, j+1, right);
> }
> }
>
> /*--------------------------------------------------------------------------------------------*/
>
> int main() {
> Element bankaccount1[10];
> int l1, r1;
>
> bankaccount1[0].setKey(26);
> bankaccount1[1].setKey(5);
> bankaccount1[2].setKey(37);
> bankaccount1[3].setKey(1);
> bankaccount1[4].setKey(61);
> bankaccount1[5].setKey(11);
> bankaccount1[6].setKey(59);
> bankaccount1[7].setKey(15);
> bankaccount1[8].setKey(48);
> bankaccount1[9].setKey(19);
> l1=0;
> r1=9;
>
> for (int i=0; i<10; i++)
> cout << bankaccount1[i].getKey() << " " ;
> cout << endl;
>
> QuickSort(bankaccount1, l1, r1);
> for (int i=0; i<10; i++)
> cout << bankaccount1[i].getKey() << " " ;
> cout << endl;
>
> return 0;
> }
> /*---------------------------------------------------------------------------------*/
> if I (or you) commnet out cout show bankaccount1 that line, it will show different results
> both result s are not what I expected(accroding to books)
> I am in 4.6.1
>
> _____________________________________________________________
> Luxmail.com
