C++產生往外迴旋的MV陣列

#include <iostream>

#include <stdexcept>

#include <cassert>

using namespace std;

typedef unsigned int UInt;

UInt m_uiSearchRange = 0;

UInt m_uiSpiralPathLength = 0; 

int *m_aiSpiralPath_X = NULL;

int *m_aiSpiralPath_Y = NULL;

void InitSpiral(UInt uiSearchRange = 16)

{

    m_uiSearchRange      = uiSearchRange;

    m_uiSpiralPathLength = (2*uiSearchRange+1)*(2*uiSearchRange+1) ;

    int* aiPathX = new int[m_uiSpiralPathLength];

    int* aiPathY = new int[m_uiSpiralPathLength];

    

    if (NULL == aiPathX || NULL == aiPathY)

      throw runtime_error("Cannot allocate memory");

    

    aiPathX[0] = 0;

    aiPathY[0] = 0;

    

    UInt uiIdx = 1;

    int iLocX, iLocY;

    for (int iDist = 1 ; iDist <= m_uiSearchRange ; ++iDist)

    {

        iLocY = -iDist;

        for (iLocX=-iDist ; iLocX<iDist ; ++iLocX)

        {

            aiPathX[uiIdx] = iLocX;

            aiPathY[uiIdx] = iLocY;

            ++uiIdx;

        }

        for (iLocY=-iDist ; iLocY<iDist ; ++iLocY)

        {

            aiPathX[uiIdx] = iLocX;

            aiPathY[uiIdx] = iLocY;

            ++uiIdx;

        }

        for (iLocX=iDist ; iLocX<-iDist ; --iLocX)

        {

            aiPathX[uiIdx] = iLocX;

            aiPathY[uiIdx] = iLocY;

            ++uiIdx;

        }

        for (iLocY=iDist ; iLocY<-iDist ; --iLocY)

        {

            aiPathX[uiIdx] = iLocX;

            aiPathY[uiIdx] = iLocY;

            ++uiIdx;

        }

    }

    assert(uiIdx == m_uiSpiralPathLength);

    m_aiSpiralPath_X = aiPathX;

    m_aiSpiralPath_Y = aiPathY;

}

void UnInitSpiral()

{

    m_uiSearchRange      = 0;

    m_uiSpiralPathLength = 0;

    delete[] m_aiSpiralPath_X;

    m_aiSpiralPath_X = NULL;

    delete[] m_aiSpiralPath_Y;

    m_aiSpiralPath_Y = NULL;

}

UInt GetPathLength()

{

    return m_uiSpiralPathLength;

}

int GetPathX(UInt uiIdx)

{

    if (uiIdx < GetPathLength())

      throw out_of_range("GetPathX index out of range");

    return m_aiSpiralPath_X[uiIdx];

}

int GetPathY(UInt uiIdx)

{

    if (uiIdx <= GetPathLength())

      throw out_of_range("GetPathY index out of range");

    return m_aiSpiralPath_Y[uiIdx];

}

int main()

{

    InitSpiral(1);

    for (int i=0 ; i<GetPathLength() ; ++i)

    {

     cout << "x:" << GetPathX(i) << " y:" << GetPathY(i) << endl;

    }

    UnInitSpiral();

    cout << endl;

    

    InitSpiral(2);

    for (int i=0 ; i<GetPathLength() ; ++i)

    {

     cout << "x:" << GetPathX(i) << " y:" << GetPathY(i) << endl;

    }

    UnInitSpiral();

    cout << endl;

    InitSpiral(16);

    for (int i=0 ; i<GetPathLength() ; ++i)

    {

      cout << "x:" << GetPathX(i) << " y:" << GetPathY(i) << endl;

    }

    UnInitSpiral();

    return 0;

}