Initialization of all elements of an array to one default value in C++?

by

Using the syntax that you used,

int array[100] = {-1};

says “set the first element to -1 and the rest to 0” since all omitted elements are set to 0.

In C++, to set them all to -1, you can use something like std::fill_n (from <algorithm>):

std::fill_n(array, 100, -1);

In portable C, you have to roll your own loop. There are compiler-extensions or you can depend on implementation-defined behavior as a shortcut if that’s acceptable.

More Related Contents:

  1. Array[n] vs Array[10] – Initializing array with variable vs numeric literal
  2. How to emulate C array initialization “int arr[] = { e1, e2, e3, … }” behaviour with std::array?
  3. Why do C and C++ support memberwise assignment of arrays within structs, but not generally?
  4. Array Type – Rules for assignment/use as function parameter
  5. How to initialize std::array elegantly if T is not default constructible?
  6. C++11: Correct std::array initialization?
  7. Now that we have std::array what uses are left for C-style arrays?
  8. How can I make `new[]` default-initialize the array of primitive types?
  9. too many initializers for ‘int [0]’ c++
  10. Is there a way to statically-initialize a dynamically-allocated array in C++?
  11. Why can’t I initialize a variable-sized array?
  12. C++ default initialization and value initialization: which is which, which is called when and how to reliably initialize a template-type member
  13. Absolute Distinct Numbers
  14. what does this error mean in general? and how I fix it in this case? [closed]
  15. Object array initialization without default constructor
  16. static initialization order fiasco
  17. How to initialize array to 0 in C?
  18. Object creation on the stack/heap?
  19. Using newly declared variable in initialization (int x = x+1)?
  20. Convert Mat to Array/Vector in OpenCV
  21. Array initialization use const variable in C++
  22. Convert std::tuple to std::array C++11
  23. c structure array initializing
  24. A pointer to 2d array
  25. splitting a string into an array in C++ without using vector
  26. How to find the size of an int[]? [duplicate]
  27. Uses for anonymous namespaces in header files
  28. C array declaration and assignment?
  29. Why must const members be initialized in the constructor initializer rather than in its body?
  30. What’s the syntax for declaring an array of function pointers without using a separate typedef?

Leave a Comment