Char array outputting correctly but not actually storing right values

Question

New to C++ and ran into another hurdle to learn from. Trying to make a simple program that reads from a file and stores the characters into a char array.

#include <iostream> #include <fstream> #include <string> #include <cctype> using namespace std; int main () { const int SIZE = 9; char arr[SIZE]; char currentChar; int numChar = 0; int i = 0; ifstream infile ("file.txt"); if (!infile) { cout << "Can not open the input file" << " This program will end."<< "\n"; return 1; } while(infile.get(arr[i])) { i++; numChar ++; } for(i=0;i<numChar;i++) { cout << arr[i]; } cout << "\n" << arr[1]; return 0; }

Contents of file.txt:

A a 9 !

Problem is that:

 for(i=0;i<numChar;i++) { cout << arr[i]; }

Has output that is identical from the file read, but when I manually checked the array elements. arr[1] is storing a white space and arr[3] ='a'. I found this out when I was trying to evaluate what type of char each element was with isalpha and isdigit statements. Why is it storing 2 elements of whitespace before getting to the next line and why does the output look correct though it actually isn't? Is there a much simpler and more efficient way to this than what I'm doing?

Thank you in advance for your help.

Because on windows each line ends with a newline and a linefeed character before moving on to the new line. — DarthRubik
– DarthRubik, Commented Apr 16, 2016 at 21:35
If you are on a different platform (say linux) it would only end in a newline, so don't get any ideas about skipping two spaces (unless you could care less about running on linux, in which case you can do what ever you want) — DarthRubik
– DarthRubik, Commented Apr 16, 2016 at 21:37
I'm actually on ubuntu 15.10. I kind of understand, correct me if i'm wrong. Because i'm reading to end of file instead of to each endline its putting them into the array. Syntax wise how could I change the while statement that reads the array so that when arr[i] = "\n" or some such thing that it ignores that and moves on and stores the array correctly? — mrbw
– mrbw, Commented Apr 16, 2016 at 21:59
@mrbw I don't know if you can actually do this, but the simplest solution would be to make all of the characters in the file on the same line. — DarthRubik
– DarthRubik, Commented Apr 16, 2016 at 22:21

Biruk Abebe · Accepted Answer · 2016-04-16 22:39:21Z

What you are reading is a new line character next to each character in your file. if you cast the characters to int when you display them you get something like:

65 //ascii code for 'A' at arr[0] 10 //ascii code for new line character(\n) at arr[1] 97 //ascii code for 'a' at arr[2] 10 ..

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