实现查找表

Question

我正在研究一个自定义数据结构，并且我目前处于 beta 测试过程中：数据将存储在一个数组中，这个数组可以表示为 4D、2D 和 1D 数组。这三个数组在联合中声明，因为它代表相同的内存寻址。这是我班级的声明：

SomeClass.h

#ifndef SomeClass_H
#define SomeClass_H

class SomeClass {
public:
    static const unsigned V1D_SIZE;   // Single Or Linear Array Representation : Size 256 - 256 Elements
    static const unsigned V2D_SIZE;   // 2D Array [16][16]                     : Size 16  - 256 Elements
    static const unsigned V4D_SIZE;   // 4D Array [4][4][4][4]                 : Size 4   - 256 Elements

    enum Index {
        HEX_UNDER_FLOW = -0x01,
        HEX_0 = 0x00,
        HEX_1 = 0x01,
        HEX_2 = 0x02,
        HEX_3 = 0x03,
        HEX_4 = 0x04,
        HEX_5 = 0x05,
        HEX_6 = 0x06,
        HEX_7 = 0x07,
        HEX_8 = 0x08,
        HEX_9 = 0x09,
        HEX_A = 0x0A,
        HEX_B = 0x0B,
        HEX_C = 0x0C,
        HEX_D = 0x0D,
        HEX_E = 0x0E,
        HEX_F = 0x0F,
        HEX_OVER_FLOW = 0x10
    }; // Index

    // Will Be Private After Testing.
    union {
        int m_p256[256];
        int m_p16[16][16];
        int m_p4[4][4][4][4];
    };

private:
    struct CrossReference {
        Index A;
        Index B;

        CrossReference() {}
        CrossReference( const Index& A_, const Index& B_ ) : A(A_), B(B_) {}
    } typedef CR;


    // Current Not Used Only Here To Illustrate A Simple Representation - May Use Or Incorporate Later
    struct Cubes {
        unsigned box;     // 0 - 3    - w
        unsigned slice;   // 0 - 15   - z 
        unsigned row;     // 0 - 15   - y
        unsigned coloumn; // 0 - 15   - x
    } m_cubes;


    CR m_cr[256];

public: 
    SomeClass();
    ~SomeClass();

    const CR& getIndexTable() const;
    void displayIndexTable() const;

private:
    // Must Be Called In Constructor First!
    void initializeCrossReference();

}; // SomeClass

#endif // SomeClass

我需要生成这个 4D 结构的坐标值对的参考查找表来实现它的 1D 版本。

为了说明索引遍历，您可以参考这些图像以获得视觉表示：

注意：图中的 {x,y,z,w} 并不代表内存中实际的 4D 数组：它只是一个可视化！在内存中，4D 数组将如下所示：array[box][slice][row][column]，此图像表示 4D 数组中的 1 个框。

注意：此图像是顶部图像中描述的所有 4 个框的 2D 视觉表示。两个图像中的彩色文本对应于适当的索引。

第二个图像是这个 4D 数组数据结构的 2D 平面网格图像表示。我们可以使用这个图像来生成这个查找表的坐标。

此图片的每四分之一代表 1 个盒子。左上（开始）是框 0，右上框 1，左下框 2，右下框 3。每个框，可以为每个切片以相同的方式分解。左上（开始）切片 0，右上切片 1，左下切片 2，右下切片 3。然后在每个切片中工作时，遍历是 row - col 并且一旦 col = 3，我们向下移动到下一行。因此，在我们完成一个切片后，我们必须根据当前切片索引来跳转我们的位置。盒子也是如此。

以下是遍历此表以生成一组十六进制索引坐标值的示例：

array[2][3][0][1] our [A,B] hex value would be [0x0C, 0x05] 
array[1][1][3][3] our [A,B] hex value would be [0x03, 0x0F]

我正在设计一个函数来生成这个查找表。我在这里手动完成了这个：

void SomeClass::initializeCrossReference() {
    //////////////////////////////////
    // Upper Half Of Grid Structure //
    //////////////////////////////////  

    //  Grid Coordinates //
    // Linear Or 1D Array Representation - Mapped From type[16][16] which is a 
    // 2D Compressed Version of type[4][4][4][4] - 
    // NOTE: This does not represent 4D Space; it represents a cluster of 4 (3D Cubes). 
    // In the declaration of the class there are two multi deminsional arrays that
    // are shared in memory through a nameless union.

    //      ROW              COL          

    // BOX - 0
    // Slice - 0
    // Row - 0                              // Column Coordinates
    m_cr[0].A  = HEX_0;  m_cr[0].B = HEX_0;  // col 0
    m_cr[1].A  = HEX_0;  m_cr[1].B = HEX_1;  // col 1
    m_cr[2].A  = HEX_0;  m_cr[2].B = HEX_2;  // col 2
    m_cr[3].A  = HEX_0;  m_cr[3].B = HEX_3;  // col 3
    // Row - 1
    m_cr[4].A  = HEX_1;  m_cr[4].B = HEX_0;
    m_cr[5].A  = HEX_1;  m_cr[5].B = HEX_1;
    m_cr[6].A  = HEX_1;  m_cr[6].B = HEX_2;
    m_cr[7].A  = HEX_1;  m_cr[7].B = HEX_3;
    // Row - 2
    m_cr[8].A  = HEX_2;  m_cr[8].B  = HEX_0;
    m_cr[9].A  = HEX_2;  m_cr[9].B  = HEX_1;
    m_cr[10].A = HEX_2;  m_cr[10].B = HEX_2;
    m_cr[11].A = HEX_2;  m_cr[11].B = HEX_3;
    // Row - 3
    m_cr[12].A = HEX_3;  m_cr[12].B = HEX_0;    
    m_cr[13].A = HEX_3;  m_cr[13].B = HEX_1;
    m_cr[14].A = HEX_3;  m_cr[14].B = HEX_2;
    m_cr[15].A = HEX_3;  m_cr[15].B = HEX_3;

    // Slice - 1
    // Row - 0
    m_cr[16].A = HEX_0;  m_cr[16].B = HEX_4;
    m_cr[17].A = HEX_0;  m_cr[17].B = HEX_5;
    m_cr[18].A = HEX_0;  m_cr[18].B = HEX_6;    
    m_cr[19].A = HEX_0;  m_cr[19].B = HEX_7;
    // Row - 1
    m_cr[20].A = HEX_1;  m_cr[20].B = HEX_4;
    m_cr[21].A = HEX_1;  m_cr[21].B = HEX_5;
    m_cr[22].A = HEX_1;  m_cr[22].B = HEX_6;
    m_cr[23].A = HEX_1;  m_cr[23].B = HEX_7;
    // Row - 2;
    m_cr[24].A = HEX_2;  m_cr[24].B = HEX_4;
    m_cr[25].A = HEX_2;  m_cr[25].B = HEX_5;
    m_cr[26].A = HEX_2;  m_cr[26].B = HEX_6;
    m_cr[27].A = HEX_2;  m_cr[27].B = HEX_7;
    // Row - 3
    m_cr[28].A = HEX_3;  m_cr[28].B = HEX_4;
    m_cr[29].A = HEX_3;  m_cr[29].B = HEX_5;
    m_cr[30].A = HEX_3;  m_cr[30].B = HEX_6;
    m_cr[31].A = HEX_3;  m_cr[31].B = HEX_7;

    // Slice - 2
    // Row - 0
    m_cr[32].A = HEX_4;  m_cr[32].B = HEX_0;
    m_cr[33].A = HEX_4;  m_cr[33].B = HEX_1;
    m_cr[34].A = HEX_4;  m_cr[34].B = HEX_2;
    m_cr[35].A = HEX_4;  m_cr[35].B = HEX_3;
    // Row - 1;
    m_cr[36].A = HEX_5;  m_cr[36].B = HEX_0;
    m_cr[37].A = HEX_5;  m_cr[37].B = HEX_1;
    m_cr[38].A = HEX_5;  m_cr[38].B = HEX_2;
    m_cr[39].A = HEX_5;  m_cr[39].B = HEX_3;
    // Row - 2;
    m_cr[40].A = HEX_6;  m_cr[40].B = HEX_0;
    m_cr[41].A = HEX_6;  m_cr[41].B = HEX_1;
    m_cr[42].A = HEX_6;  m_cr[42].B = HEX_2;
    m_cr[43].A = HEX_6;  m_cr[43].B = HEX_3;
    // Row - 3
    m_cr[44].A = HEX_7;  m_cr[44].B = HEX_0;
    m_cr[45].A = HEX_7;  m_cr[45].B = HEX_1;
    m_cr[46].A = HEX_7;  m_cr[46].B = HEX_2;
    m_cr[47].A = HEX_7;  m_cr[47].B = HEX_3;

    // Slice - 3
    // Row - 0
    m_cr[48].A = HEX_4;  m_cr[48].B = HEX_4;
    m_cr[49].A = HEX_4;  m_cr[49].B = HEX_5;
    m_cr[50].A = HEX_4;  m_cr[50].B = HEX_6;
    m_cr[51].A = HEX_4;  m_cr[51].B = HEX_7;
    // Row - 1
    m_cr[52].A = HEX_5;  m_cr[52].B = HEX_4;
    m_cr[53].A = HEX_5;  m_cr[53].B = HEX_5;
    m_cr[54].A = HEX_5;  m_cr[54].B = HEX_6;
    m_cr[55].A = HEX_5;  m_cr[55].B = HEX_7;
    // Row - 2;
    m_cr[56].A = HEX_6;  m_cr[56].B = HEX_4;
    m_cr[57].A = HEX_6;  m_cr[57].B = HEX_5;
    m_cr[58].A = HEX_6;  m_cr[58].B = HEX_6;
    m_cr[59].A = HEX_6;  m_cr[59].B = HEX_7;
    // Row - 3
    m_cr[60].A = HEX_7;  m_cr[60].B = HEX_4;
    m_cr[61].A = HEX_7;  m_cr[61].B = HEX_5;
    m_cr[62].A = HEX_7;  m_cr[62].B = HEX_6;
    m_cr[63].A = HEX_7;  m_cr[63].B = HEX_7;

    // BOX - 1
    // Slice - 0
    // Row - 0
    m_cr[64].A = HEX_0;  m_cr[64].B = HEX_8;
    m_cr[65].A = HEX_0;  m_cr[65].B = HEX_9;
    m_cr[66].A = HEX_0;  m_cr[66].B = HEX_A;
    m_cr[67].A = HEX_0;  m_cr[67].B = HEX_B;
    // Row - 1
    m_cr[68].A = HEX_1;  m_cr[68].B = HEX_8;
    m_cr[69].A = HEX_1;  m_cr[69].B = HEX_9;
    m_cr[70].A = HEX_1;  m_cr[70].B = HEX_A;
    m_cr[71].A = HEX_1;  m_cr[71].B = HEX_B;
    // Row - 2
    m_cr[72].A = HEX_2;  m_cr[72].B = HEX_8;
    m_cr[73].A = HEX_2;  m_cr[73].B = HEX_9;
    m_cr[74].A = HEX_2;  m_cr[74].B = HEX_A;
    m_cr[75].A = HEX_2;  m_cr[75].B = HEX_B;
    // Row - 3
    m_cr[76].A = HEX_3;  m_cr[76].B = HEX_8;
    m_cr[77].A = HEX_3;  m_cr[77].B = HEX_9;
    m_cr[78].A = HEX_3;  m_cr[78].B = HEX_A;
    m_cr[79].A = HEX_3;  m_cr[79].B = HEX_B;

    // Slice - 1
    // Row - 0
    m_cr[80].A = HEX_0;  m_cr[80].B = HEX_C;
    m_cr[81].A = HEX_0;  m_cr[81].B = HEX_D;
    m_cr[82].A = HEX_0;  m_cr[82].B = HEX_E;
    m_cr[83].A = HEX_0;  m_cr[83].B = HEX_F;
    // Row - 1
    m_cr[84].A = HEX_1;  m_cr[84].B = HEX_C;
    m_cr[85].A = HEX_1;  m_cr[85].B = HEX_D;
    m_cr[86].A = HEX_1;  m_cr[86].B = HEX_E;
    m_cr[87].A = HEX_1;  m_cr[87].B = HEX_F;
    // Row - 2
    m_cr[88].A = HEX_2;  m_cr[88].B = HEX_C;
    m_cr[89].A = HEX_2;  m_cr[89].B = HEX_D;
    m_cr[90].A = HEX_2;  m_cr[90].B = HEX_E;
    m_cr[91].A = HEX_2;  m_cr[91].B = HEX_F;
    // Row - 3
    m_cr[92].A = HEX_3;  m_cr[92].B = HEX_C;
    m_cr[93].A = HEX_3;  m_cr[93].B = HEX_D;
    m_cr[94].A = HEX_3;  m_cr[94].B = HEX_E;
    m_cr[95].A = HEX_3;  m_cr[95].B = HEX_F;

    // Slice - 2
    // Row - 0
    m_cr[96].A = HEX_4;  m_cr[96].B = HEX_8;
    m_cr[97].A = HEX_4;  m_cr[97].B = HEX_9;
    m_cr[98].A = HEX_4;  m_cr[98].B = HEX_A;
    m_cr[99].A = HEX_4;  m_cr[99].B = HEX_B;
    // Row - 1
    m_cr[100].A = HEX_5;  m_cr[100].B = HEX_8;
    m_cr[101].A = HEX_5;  m_cr[101].B = HEX_9;
    m_cr[102].A = HEX_5;  m_cr[102].B = HEX_A;
    m_cr[103].A = HEX_5;  m_cr[103].B = HEX_B;
    // Row - 2
    m_cr[104].A = HEX_6;  m_cr[104].B = HEX_8;
    m_cr[105].A = HEX_6;  m_cr[105].B = HEX_9;
    m_cr[106].A = HEX_6;  m_cr[106].B = HEX_A;
    m_cr[107].A = HEX_6;  m_cr[107].B = HEX_B;
    // Row - 3
    m_cr[108].A = HEX_7;  m_cr[108].B = HEX_8;
    m_cr[109].A = HEX_7;  m_cr[109].B = HEX_9;
    m_cr[110].A = HEX_7;  m_cr[110].B = HEX_A;
    m_cr[111].A = HEX_7;  m_cr[111].B = HEX_B;

    // Slice - 3
    // Row - 0
    m_cr[112].A = HEX_4;  m_cr[112].B = HEX_C;
    m_cr[113].A = HEX_4;  m_cr[113].B = HEX_D;
    m_cr[114].A = HEX_4;  m_cr[114].B = HEX_E;
    m_cr[115].A = HEX_4;  m_cr[115].B = HEX_F;
    // Row - 1
    m_cr[116].A = HEX_5;  m_cr[116].B = HEX_C;
    m_cr[117].A = HEX_5;  m_cr[117].B = HEX_D;
    m_cr[118].A = HEX_5;  m_cr[118].B = HEX_E;
    m_cr[119].A = HEX_5;  m_cr[119].B = HEX_F;
    // Row - 2
    m_cr[120].A = HEX_6;  m_cr[120].B = HEX_C;
    m_cr[121].A = HEX_6;  m_cr[121].B = HEX_D;
    m_cr[122].A = HEX_6;  m_cr[122].B = HEX_E;
    m_cr[123].A = HEX_6;  m_cr[123].B = HEX_F;
    // Row - 3
    m_cr[124].A = HEX_7;  m_cr[124].B = HEX_C;
    m_cr[125].A = HEX_7;  m_cr[125].B = HEX_D;
    m_cr[126].A = HEX_7;  m_cr[126].B = HEX_E;
    m_cr[127].A = HEX_7;  m_cr[127].B = HEX_F;

    //////////////////////////////////
    // Lower Half Of Grid Structure //
    //////////////////////////////////

    // Box - 2
    // Slice - 0
    // Row - 0
    m_cr[128].A = HEX_8;  m_cr[128].B = HEX_0;  // col 0
    m_cr[129].A = HEX_8;  m_cr[129].B = HEX_1;  // col 1
    m_cr[130].A = HEX_8;  m_cr[130].B = HEX_2;  // col 2
    m_cr[131].A = HEX_8;  m_cr[131].B = HEX_3;  // col 3
    // Row - 1
    m_cr[132].A = HEX_9;  m_cr[132].B = HEX_0;
    m_cr[133].A = HEX_9;  m_cr[133].B = HEX_1;
    m_cr[134].A = HEX_9;  m_cr[134].B = HEX_2;
    m_cr[135].A = HEX_9;  m_cr[135].B = HEX_3;
    // Row - 2
    m_cr[136].A = HEX_A;  m_cr[136].B = HEX_0;
    m_cr[137].A = HEX_A;  m_cr[137].B = HEX_1;
    m_cr[138].A = HEX_A;  m_cr[138].B = HEX_2;
    m_cr[139].A = HEX_A;  m_cr[139].B = HEX_3;
    // Row - 3
    m_cr[140].A = HEX_B;  m_cr[140].B = HEX_0;
    m_cr[141].A = HEX_B;  m_cr[141].B = HEX_1;
    m_cr[142].A = HEX_B;  m_cr[142].B = HEX_2;
    m_cr[143].A = HEX_B;  m_cr[143].B = HEX_3;

    // Slice - 1
    // Row - 0
    m_cr[144].A = HEX_8;  m_cr[144].B = HEX_4;
    m_cr[145].A = HEX_8;  m_cr[145].B = HEX_5;
    m_cr[146].A = HEX_8;  m_cr[146].B = HEX_6;
    m_cr[147].A = HEX_8;  m_cr[147].B = HEX_7;
    // Row - 1
    m_cr[148].A = HEX_9;  m_cr[148].B = HEX_4;
    m_cr[149].A = HEX_9;  m_cr[149].B = HEX_5;
    m_cr[150].A = HEX_9;  m_cr[150].B = HEX_6;
    m_cr[151].A = HEX_9;  m_cr[151].B = HEX_7;
    // Row - 2;
    m_cr[152].A = HEX_A;  m_cr[152].B = HEX_4;
    m_cr[153].A = HEX_A;  m_cr[153].B = HEX_5;
    m_cr[154].A = HEX_A;  m_cr[154].B = HEX_6;
    m_cr[155].A = HEX_A;  m_cr[155].B = HEX_7;
    // Row - 3
    m_cr[156].A = HEX_B;  m_cr[156].B = HEX_4;
    m_cr[157].A = HEX_B;  m_cr[157].B = HEX_5;
    m_cr[158].A = HEX_B;  m_cr[158].B = HEX_6;
    m_cr[159].A = HEX_B;  m_cr[159].B = HEX_7;

    // Slice - 2
    // Row - 0
    m_cr[160].A = HEX_C;  m_cr[160].B = HEX_0;
    m_cr[161].A = HEX_C;  m_cr[161].B = HEX_1;
    m_cr[162].A = HEX_C;  m_cr[162].B = HEX_2;
    m_cr[163].A = HEX_C;  m_cr[163].B = HEX_3;
    // Row - 1;
    m_cr[164].A = HEX_D;  m_cr[164].B = HEX_0;
    m_cr[165].A = HEX_D;  m_cr[165].B = HEX_1;
    m_cr[166].A = HEX_D;  m_cr[166].B = HEX_2;
    m_cr[167].A = HEX_D;  m_cr[167].B = HEX_3;
    // Row - 2;
    m_cr[168].A = HEX_E;  m_cr[168].B = HEX_0;
    m_cr[169].A = HEX_E;  m_cr[169].B = HEX_1;
    m_cr[170].A = HEX_E;  m_cr[170].B = HEX_2;
    m_cr[171].A = HEX_E;  m_cr[171].B = HEX_3;
    // Row - 3
    m_cr[172].A = HEX_F;  m_cr[172].B = HEX_0;
    m_cr[173].A = HEX_F;  m_cr[173].B = HEX_1;
    m_cr[174].A = HEX_F;  m_cr[174].B = HEX_2;
    m_cr[175].A = HEX_F;  m_cr[175].B = HEX_3;

    // Slice - 3
    // Row - 0
    m_cr[176].A = HEX_C;  m_cr[176].B = HEX_4;
    m_cr[177].A = HEX_C;  m_cr[177].B = HEX_5;
    m_cr[178].A = HEX_C;  m_cr[178].B = HEX_6;
    m_cr[179].A = HEX_C;  m_cr[179].B = HEX_7;
    // Row - 1
    m_cr[180].A = HEX_D;  m_cr[180].B = HEX_4;
    m_cr[181].A = HEX_D;  m_cr[181].B = HEX_5;
    m_cr[182].A = HEX_D;  m_cr[182].B = HEX_6;
    m_cr[183].A = HEX_D;  m_cr[183].B = HEX_7;
    // Row - 2;
    m_cr[184].A = HEX_E;  m_cr[184].B = HEX_4;
    m_cr[185].A = HEX_E;  m_cr[185].B = HEX_5;
    m_cr[186].A = HEX_E;  m_cr[186].B = HEX_6;
    m_cr[187].A = HEX_E;  m_cr[187].B = HEX_7;
    // Row - 3
    m_cr[188].A = HEX_F;  m_cr[188].B = HEX_4;
    m_cr[189].A = HEX_F;  m_cr[189].B = HEX_5;
    m_cr[190].A = HEX_F;  m_cr[190].B = HEX_6;
    m_cr[191].A = HEX_F;  m_cr[191].B = HEX_7;

    // BOX - 3
    // Slice - 0
    // Row - 0
    m_cr[192].A = HEX_8;  m_cr[192].B = HEX_8;
    m_cr[193].A = HEX_8;  m_cr[193].B = HEX_9;
    m_cr[194].A = HEX_8;  m_cr[194].B = HEX_A;
    m_cr[195].A = HEX_8;  m_cr[195].B = HEX_B;
    // Row - 1
    m_cr[196].A = HEX_9;  m_cr[196].B = HEX_8;
    m_cr[197].A = HEX_9;  m_cr[197].B = HEX_9;
    m_cr[198].A = HEX_9;  m_cr[198].B = HEX_A;
    m_cr[199].A = HEX_9;  m_cr[199].B = HEX_B;
    // Row - 2
    m_cr[200].A = HEX_A;  m_cr[200].B = HEX_8;
    m_cr[201].A = HEX_A;  m_cr[201].B = HEX_9;
    m_cr[202].A = HEX_A;  m_cr[202].B = HEX_A;
    m_cr[203].A = HEX_A;  m_cr[203].B = HEX_B;
    // Row - 3
    m_cr[204].A = HEX_B;  m_cr[204].B = HEX_8;
    m_cr[205].A = HEX_B;  m_cr[205].B = HEX_9;
    m_cr[206].A = HEX_B;  m_cr[206].B = HEX_A;
    m_cr[207].A = HEX_B;  m_cr[207].B = HEX_B;

    // Slice - 1
    // Row - 0
    m_cr[208].A = HEX_8;  m_cr[208].B = HEX_C;
    m_cr[209].A = HEX_8;  m_cr[209].B = HEX_D;
    m_cr[210].A = HEX_8;  m_cr[210].B = HEX_E;
    m_cr[211].A = HEX_8;  m_cr[211].B = HEX_F;
    // Row - 1
    m_cr[212].A = HEX_9;  m_cr[212].B = HEX_C;
    m_cr[213].A = HEX_9;  m_cr[213].B = HEX_D;
    m_cr[214].A = HEX_9;  m_cr[214].B = HEX_E;
    m_cr[215].A = HEX_9;  m_cr[215].B = HEX_F;
    // Row - 2
    m_cr[216].A = HEX_A;  m_cr[216].B = HEX_C;
    m_cr[217].A = HEX_A;  m_cr[217].B = HEX_D;
    m_cr[218].A = HEX_A;  m_cr[218].B = HEX_E;
    m_cr[219].A = HEX_A;  m_cr[219].B = HEX_F;
    // Row - 3
    m_cr[220].A = HEX_B;  m_cr[220].B = HEX_C;
    m_cr[221].A = HEX_B;  m_cr[221].B = HEX_D;
    m_cr[222].A = HEX_B;  m_cr[222].B = HEX_E;
    m_cr[223].A = HEX_B;  m_cr[223].B = HEX_F;

    // Slice - 2
    // Row - 0
    m_cr[224].A = HEX_C;  m_cr[224].B = HEX_8;
    m_cr[225].A = HEX_C;  m_cr[225].B = HEX_9;
    m_cr[226].A = HEX_C;  m_cr[226].B = HEX_A;
    m_cr[227].A = HEX_C;  m_cr[227].B = HEX_B;
    // Row - 1
    m_cr[228].A = HEX_D;  m_cr[228].B = HEX_8;
    m_cr[229].A = HEX_D;  m_cr[229].B = HEX_9;
    m_cr[230].A = HEX_D;  m_cr[230].B = HEX_A;
    m_cr[231].A = HEX_D;  m_cr[231].B = HEX_B;
    // Row - 2
    m_cr[232].A = HEX_E;  m_cr[232].B = HEX_8;
    m_cr[233].A = HEX_E;  m_cr[233].B = HEX_9;
    m_cr[234].A = HEX_E;  m_cr[234].B = HEX_A;
    m_cr[235].A = HEX_E;  m_cr[235].B = HEX_B;
    // Row - 3
    m_cr[236].A = HEX_F;  m_cr[236].B = HEX_8;
    m_cr[237].A = HEX_F;  m_cr[237].B = HEX_9;
    m_cr[238].A = HEX_F;  m_cr[238].B = HEX_A;
    m_cr[239].A = HEX_F;  m_cr[239].B = HEX_B;

    // Slice - 3
    // Row - 0
    m_cr[240].A = HEX_C;  m_cr[240].B = HEX_C;
    m_cr[241].A = HEX_C;  m_cr[241].B = HEX_D;
    m_cr[242].A = HEX_C;  m_cr[242].B = HEX_E;
    m_cr[243].A = HEX_C;  m_cr[243].B = HEX_F;
    // Row - 1
    m_cr[244].A = HEX_D;  m_cr[244].B = HEX_C;
    m_cr[245].A = HEX_D;  m_cr[245].B = HEX_D;
    m_cr[246].A = HEX_D;  m_cr[246].B = HEX_E;
    m_cr[247].A = HEX_D;  m_cr[247].B = HEX_F;
    // Row - 2
    m_cr[248].A = HEX_E;  m_cr[248].B = HEX_C;
    m_cr[249].A = HEX_E;  m_cr[249].B = HEX_D;
    m_cr[250].A = HEX_E;  m_cr[250].B = HEX_E;
    m_cr[251].A = HEX_E;  m_cr[251].B = HEX_F;
    // Row - 3
    m_cr[252].A = HEX_F;  m_cr[252].B = HEX_C;
    m_cr[253].A = HEX_F;  m_cr[253].B = HEX_D;
    m_cr[254].A = HEX_F;  m_cr[254].B = HEX_E;
    m_cr[255].A = HEX_F;  m_cr[255].B = HEX_F;

} // initializeCrossReference

正如你所见，这个函数很长，而且可读性不强。我试图找出一种以优雅的方式实现此功能的方法，这就是我卡住的地方。如何使用 for loop/s 和一些 if 语句（如果需要）在几行代码中生成这种模式？

最终我想将这些 [A,B] 坐标压缩成一个无符号字符，就好像 [A,B] = [0x0C,0x08] 它将被存储为 0xC8 作为一个字节而不是一对枚举。

编辑 - 添加一个新图像，有助于了解我如何生成我的坐标对以及它们在我的查找数组中的确切顺序。

注意：这个问题是我正在接受的帖子，至于这里的老问题Custom Data Structure: Implementing an algorithim to generate a lookup table [duplicate]现在是一个死帖，请参考这个是正确的。昨晚当我尝试继续编辑旧浏览器时，我的浏览器出现了问题。我本来打算删除它，但出于历史目的，我会把它留在那里，让管理人员决定是否删除它。

Answer 1

例如，像这样：

for (int i = 0; i < 256; ++i) {
    int cube = i / 64;
    int slice = (i % 64) / 16;
    int row = (i % 16) / 4;
    int col = i % 4;
    m_cr[i].A = cube / 2 * 8 + slice / 2 * 4 + row;
    m_cr[i].B = cube % 2 * 8 + slice % 2 * 4 + col;
}

Answer 2

盯着查表看了几分钟（而且只看查表中的原始数据，看不懂图形），我相信下面的例子会生成你的查表。

正如我告诉你的in your first question，大部分问题都是无关紧要的。如果您摆脱了问题的前 3/4，那么很快就会有人提出答案。有时了解一点数据的含义确实会有所帮助，但在这里，它似乎比其他任何事情都更让人分心。

无论如何，首先要做的是摆脱enum。它不会增加任何价值，只会妨碍。只需使用自然的十六进制数，仅此而已。话虽如此，你用自己的代码来调整它应该是微不足道的：

#include <iostream>

int main()
{
    for (int n=0; n<256; ++n)
    {
        int a = ((((n >> 5) & 1) << 2) | (n & 0x80) >> 4) | ((n >> 2) & 3);
        int b = (n & 3) | (((n >> 4) & 1) << 2) |
            (((n >> 6) & 1) << 3);

        std::cout << n << ": a=" << a << " b=" << b << std::endl;
    }
}

我有一种烦人的感觉，认为这可以进一步简化，也许其他人可以做出改进，但无论如何，对于A，此输出似乎与原始十六进制值匹配和B，在您的查找表中。

Answer 3

首先将 HEX_ 更改为数组。然后，查看各个块并将它们变成循环。由于您的.A和.B是互斥的，我们可能会分开处理。

这是一个可以用来帮助初始化 A 的“函数”：

void InitializeA(CrossReference arr[])
{
    InitializeABlock(arr, 0x00, 0x00);
    InitializeABlock(arr, 0x10, 0x00);
    InitializeABlock(arr, 0x20, 0x04);
    InitializeABlock(arr, 0x30, 0x04);
    InitializeABlock(arr, 0x40, 0x00);
    InitializeABlock(arr, 0x50, 0x00);
    InitializeABlock(arr, 0x60, 0x04);
    InitializeABlock(arr, 0x70, 0x04);

    InitializeABlock(arr, 0x80, 0x08);
    InitializeABlock(arr, 0x90, 0x08);
    InitializeABlock(arr, 0xA0, 0x10);
    InitializeABlock(arr, 0xB0, 0x10);
    InitializeABlock(arr, 0xC0, 0x08);
    InitializeABlock(arr, 0xD0, 0x08);
    InitializeABlock(arr, 0xE0, 0x10);
    InitializeABlock(arr, 0xF0, 0x10);
}

void InitializeABlock(CrossReference arr[], int idxStart, int hexStart)
{
    for(int j = hexStart; j < hexStart + 4; j++)
    {
        int baseIdx = idxStart + 4 * (j - hexStart);

        for(int i = 0; i < 4; i++)
        {
            arr[baseIdx + i].A = j;
        }
    }
}

B 的实现非常相似：

void InitializeB(CrossReference arr[])
{
    InitializeBBlock(arr, 0x00, 0x00);
    InitializeBBlock(arr, 0x10, 0x00);
    InitializeBBlock(arr, 0x20, 0x04);
    InitializeBBlock(arr, 0x30, 0x04);
    InitializeBBlock(arr, 0x40, 0x00);
    InitializeBBlock(arr, 0x50, 0x00);
    InitializeBBlock(arr, 0x60, 0x04);
    InitializeBBlock(arr, 0x70, 0x04);

    InitializeBBlock(arr, 0x80, 0x08);
    InitializeBBlock(arr, 0x90, 0x08);
    InitializeBBlock(arr, 0xA0, 0x10);
    InitializeBBlock(arr, 0xB0, 0x10);
    InitializeBBlock(arr, 0xC0, 0x08);
    InitializeBBlock(arr, 0xD0, 0x08);
    InitializeBBlock(arr, 0xE0, 0x10);
    InitializeBBlock(arr, 0xF0, 0x10);
}

void InitializeBBlock(CrossReference arr[], int idxStart, int hexStart)
{
    for(int j = idxStart; j < idxStart + 4; j++)
    {
        int baseIdx = idxStart + 4 * (j - idxStart);

        for(int i = 0; i < 4; i++)
        {
            arr[baseIdx + i].A = i + hexStart;
        }
    }
}

当然，您可以进一步压缩它。 ;)