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Init array with a non-zero value

This is embarrasing, but I've always thought:

int variable[10] = {9};

will init all items to 9. But it does not.

Any cool way to init to a non-zero value besides a for-loop?

Thanks in advance.

Re: Init array with a non-zero value

#include <algorithm>
 
...
 
int variable[10];
std::fill_n(variable, 10, 9);

still just a loop under the hood

Re: Init array with a non-zero value

For smaller arrays, you can do this

int variable[5] = {9,9,9,9,9};

Re: Init array with a non-zero value

Quote:

Originally Posted by kurt

This is embarrasing, but I've always thought:

int variable[10] = {9};

will init all items to 9. But it does not.

When you initialize an array like that, it will initialize all elements you specify to the values you give, and any remaining elements will be initialized to zero (for fundamental types) or with the default constructor (for objects). If the array does not have a subscript, then the number of elements is taken from the number of values you provide:

// all set to 9
int array1[10] = {9, 9, 9, 9, 9, 9, 9, 9, 9, 9};
 
// first three set to 9, rest set to 0
int array2[10] = {9, 9, 9};
 
// five elements, all set to 9
int array3[] = {9, 9, 9, 9, 9};

Re: Init array with a non-zero value

memset is a function that can be pretty handy sometimes. Even thought it may not function as expected with your "int" it is good to know about it when you are using char's.
http://www.cplusplus.com/reference/c...ng/memset.html