c++ - 实现查找表

标签 c++ algorithm indexing lookup lookup-tables

我正在开发一个自定义数据结构,目前正在进行 beta 测试过程:数据将存储在一个数组中,并且该数组可以表示为 4D、2D 和 1D 数组。这三个数组在 union 中声明,因为它代表相同的内存寻址。这是对我的类(class)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 结构的坐标值对的引用查找表来实现其 1D 版本。

为了说明索引遍历,您可以引用以下图像进行直观表示:

3D Visual注意:此图像中的 {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],该图像代表 4D 数组中的 1 个框。

2D Visual 1D LookUp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。

第二个图像是此 4D 数组数据结构的 2D 平面网格图像表示。我们可以使用该图像来生成该查找表的坐标。

此图像的每个四分之一代表 1 个盒子。左上(起始)是框 0,右上框 1,左下框 2,右下框 3。每个框都可以以相同的方式分解为每个切片。左上(起始)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,一旦 col = 3,我们向下移动到下一行。因此,在完成单个切片后,我们必须根据当前切片索引跳转到我们的位置。盒子也是如此。

以下是遍历此表以生成一组十六进制表示法的索引坐标值的示例:

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此操作:

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

正如你所看到的,这个函数很长,而且可读性不太好。我试图找出一种以优雅的方式实现此功能的方法,这就是我陷入困境的地方。我如何使用 for 循环和一些 if 语句(如果需要)在几行代码内生成此模式?

最终我想将这些 [A,B] 坐标压缩为单个无符号字符,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,这应该有助于理解我如何生成坐标对以及它们在查找数组中必须处于的确切顺序。

Improved Image

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]现在是一篇死帖子,请将此帖子视为正确的帖子。昨晚,当我试图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,我会将其保留在那里,并让管理部门决定是否删除它。

最佳答案

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;
}

关于c++ - 实现查找表,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36416290/

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