"Read Primer" 20.<3.6> multidimensional array Page112

A multi-bit array in C + +, which is strictly an array of arrays.

int ia[3[4// size 3 array, each    element is an array with 4 integers //  An array of size 10, Each element is an array of size    20,// The elements of these arrays are arrays of 30 integers    int arr[[  [+] = {0//  Initialize all elements to 0

Initializing a multidimensional array

    intia1[3][4] = {        {0,1,2,3},        {4,5,6,7},        {8,9,Ten, One}    }; //The following statement is equivalent to the above initialization    intia2[3][4] = {0,1,2,3,4,5,6,7,8,9,Ten, One};

Subscript References for multidimensional arrays

    //iterate over multidimensional arrays with multiple loops     for(size_t i =0; I! =3; ++i) { for(size_t j =0; J! =4; ++j) {cout<<"Row is"<< I <<", Col is"<< J <<", value is:"<< Ia1[i][j] <<Endl; }    }        //use the scope for statement to traverse     for(Auto &row:ia1) {         for(Auto &Col:row) {cout<<"value is:"<< Ia1[i][j] <<Endl; }    }

Pointers and multidimensional arrays

The declaration of a level two element in a multidimensional array requires extra attention, and of course we can use auto instead of this declaration, or use typedef to make a declaration multiple times.

    int ia[3[4];     // an array of size 3, each containing an array    of 4 integers int (*p) [4//  P points to an array containing 4 integers (pointers to arrays)    //  int *p[4];     // an array of integer pointers (arrays of pointers)    p = &ia[2];        // p points to the tail element of the IA    

All the code for this section

#include <iostream>usingstd::cout;usingStd::endl;intMain () {intia[3][4];//an array of size 3, each containing an array of 4 integers//an array of size 10, with each element being an array of size 20,//The elements of these arrays are arrays that contain 30 integers    intarr[Ten][ -][ -] = {0};//initialize all elements to 0            intia1[3][4] = {        {0,1,2,3},        {4,5,6,7},        {8,9,Ten, One}    }; //The following statement is equivalent to the above initialization    intia2[3][4] = {0,1,2,3,4,5,6,7,8,9,Ten, One}; //iterate over multidimensional arrays with multiple loops     for(size_t i =0; I! =3; ++i) { for(size_t j =0; J! =4; ++j) {cout<<"Row is"<< I <<", Col is"<< J <<", value is:"<< Ia1[i][j] <<Endl; }    }        //use the scope for statement to traverse through the auto type to simplify the code     for(Auto &row:ia1) {         for(Auto &Col:row) {cout<<"value is:"<< Col <<Endl; }    }        intia3[3][4];//an array of size 3, each containing an array of 4 integers    int(*p) [4] = IA3;//p points to an array containing 4 integers (pointers to arrays)//int *p[4]; //an array of integer pointers (arrays of pointers)p = &ia3[2];//p points to the tail element of the IA        }

"Read Primer" 20.<3.6> multidimensional array Page112