C / C++ / MFC

void CFeaturesDialog::OnEnChangeMfceditbrowse1()
{
	CString str;
	m_browser.GetWindowTextW(str); //CMFCEditBrowseCtrl m_browser;
	
}

void CDataDialog::OnBnClickedOk()
{
	CStdioFile file(L"over1.txt", CFile::modeCreate |
		CFile::modeWrite);
}

This is a simplified version of the problem.

We have an array of numbers (between 0 and X-1), at each round, we choose a range of numbers that we compare and only promote the biggest one and eliminate the rest. At each round, we need to output the *original* indices of the numbers that have been eliminated.

This is best explained using an example:

Here is the input:

    8 // X represents the size of the array, 2 ≤ X ≤ 100000
    4 // Y represents the number of elimination rounds 1 ≤ Y ≤ X−1
    1 0 3 6 2 4 7 5 // the numbers
    1 3
    2 4
    1 3
    0 1

Output: 4 lines, the original index of the losers at each round

    1 2
    4 5
    3 7
    0

Here is a diagram of how the output was obtained, `[]` means the numbers inside the brackets are the ones being compared.

    1 [0 3 6] 2 4 7 5 // output 1 2 because 0 and 3 were eliminated
    1 6 [2 4 7] 5 // output 4 5 because 4 and 2 were eliminated
    1 [6 7 5] // output 3 7 because 7 and 5 were eliminated
    [1 7] // output 0 because 1 was eliminated
    7

The basic idea is that we want to output the original indices of the number eliminated at each round.

**Approach:**

Model each number as a pair, with the second entry representing the original index. So we have the following:

    (1,0) [(0,1) (3,2) (6,3)] (2,4) (4,5) (7,6) (5,7) // 1 2
    (1,0) (6,3) [(2,4) (4,5) (7,6)] (5,7) // 4 5
    (1,0) [(6,3) (7,6) (5,7)] // 3 7
    [(1,0) (7,6)] // 0
    [7,6]

Is this a promising approach? What is the best way to complement it efficiently?

Is there a better, more efficient approach that is easier to implement?