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2D array values C++

I wanted to declare a 2D array and assign values to it, without running a for loop.

I thought I could used the following idea

int array[5] = {1,2,3,4,5}; 

Which works fine to initialize the 2D array as well. But apparently my compiler doesn't like this.

/*  1   8  12  20  25  5   9  13  24  26 */  #include <iostream.h>  int main() {     int arr[2][5] = {0};   // This actually initializes everything to 0.     arr [1] [] = {1,8,12,20,25}; // Line 11     arr [2] [] = {5,9,13,24,26};     return 0; } 

J:\CPP\Grid>bcc32.exe Grid.cpp

Borland C++ 5.5.1 for Win32 Copyright (c) 1993, 2000 Borland

Grid.cpp:

Error E2188 Grid.cpp 11: Expression syntax in function main()

Error E2188 Grid.cpp 12: Expression syntax in function main()

Warning W8004 Grid.cpp 14: 'arr' is assigned a value that is never used in funct ion main()

* 2 errors in Compile *

Please help as to what is the right way to initialize the 2d array with my set of values.

like image 998
Kingkong Jnr Avatar asked Feb 12 '11 23:02

Kingkong Jnr


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1 Answers

Like this:

int main() {     int arr[2][5] =     {         {1,8,12,20,25},         {5,9,13,24,26}     }; } 

This should be covered by your C++ textbook: which one are you using?

Anyway, better, consider using std::vector or some ready-made matrix class e.g. from Boost.

like image 181
Cheers and hth. - Alf Avatar answered Oct 10 '22 01:10

Cheers and hth. - Alf