Char array takes only a part of the string

Question

Disclaimer: I have to use char arrays instead of strings because this is a part of my home assignment.

I try to input a string from a keyboard into a char array. However, it always inputs only the first word, independently of how I declare the array. Two examples of when I do this:

#include <iostream>
int main() {
    char arr[] = "";
    std::cin >> arr;
    return 0; 
}

and

#include <iostream>
int main() {
    char* arr = new char[100];
    std::cin >> arr;
    return 0;
}

Both times I expect the string I enter to be stored in arr fully, but it stores only the first word: all the symbols before the first space.

Take a look at [this](https://stackoverflow.com/q/19898510/8708630) post. — Vineet Bhat, Jan 19 '18 at 05:32
You need to make sure your array is large enough. In your first example it only has space for one character. Which for a null-terminated string would be the null terminator. — juanchopanza, Jan 19 '18 at 05:33
@juanchopanza No, it expands automatically, it seems--when I run the first example, it stores the first word no matter how many characters are there. The problem is in that I need to use getline(), as I was kindly informed in the first comment. — Taisia Sharapova, Jan 19 '18 at 05:35
No, arrays don't expand automatically. What happens is C++ allows you to go out of bounds. If you go far enough you may even get a seg fault. — juanchopanza, Jan 19 '18 at 05:37
@LưuVĩnhPhúc Fixed now (hopefully). It's not a part of my actual code, I just wrote these examples from memory and forgot a couple of things. — Taisia Sharapova, Jan 19 '18 at 06:32

score 0 · Accepted Answer · answered Jan 19 '18 at 06:19

0

If you don't use std::cin.getline() it will assume next variable to enter after a space.

answered Jan 19 '18 at 06:19

ShivCK

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Char array takes only a part of the string

1 Answers1