How to initialize all elements in an array to the same number in C++

Question

I'm trying to initialize an int array with everything set at -1.

I tried the following, but it doesn't work. It only sets the first value at -1.

int directory[100] = {-1}; 

Why doesn't it work right?

Answer 1

I'm surprised at all the answers suggesting vector. They aren't even the same thing!

Use std::fill, from <algorithm>:

int directory[100]; std::fill(directory, directory + 100, -1); 

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Not concerned with the question directly, but you might want a nice helper function when it comes to arrays:

template <typename T, size_t N> T* end(T (&pX)[N]) {     return pX + N; } 

Giving:

int directory[100]; std::fill(directory, end(directory), -1); 

So you don't need to list the size twice.