Why isn't my infile.get working?

[ErinCorona]

My program is supposed to read in numbers from a file, one character at a time.
When ran, the program correctly identifies that the first line only has one character, but it does not seem to have that it is an 8. For some reason, I get back the number 10, after I try to convert it from a char data type to an int data type. Teacher said the way to do this was to subtract a 0 from the character. What am I doing wrong?

//***********************************************************************************
//This is a program that will add two numbers and print out those numbers as well
//as their sum.  The program should handle up to 25 digit integer numbers.  The
//input is found in BigNumberV2.txt.  The format should be one number per line, and
//should be all right hand justified, and labeled, without showing any leading zeros.
//***********************************************************************************

#include <iostream>    //Header files
#include <fstream>
#include <cmath>

using namespace std;

//File descriptors
ifstream infile;
ofstream outfile;

int main()
{
    infile.open("BigNumbersV2.txt"); //Open text file to read from
    outfile.open("answers.out");    //Open textfile to write to
    if (!infile) //If input file did not open correctly
    {
        cout << "Error opening input file." << endl; //Display error message
        return 0; //Quit
    }
    if (!outfile) //If outfile does not open
    {
        cout << "Error opening output file." << endl; //Display error message
        return 0;  //Quit
    }
    int chary[25];   //Declare array for reading in numbers by character
    int num1ary[25]; //Declare array for storing number 1
    int num2ary[25]; //Declare array for storing number 2
    int sumary[25];  //Declare array for storing sum
    int i = 0;  //Declare and initialize an array position holder
    char ch;    //Declare variable for reading in each character from infile

    //Read-in the number
    infile.get(ch); //Read in first character
    while ( ch != '\n')  //While read-in value is not a new line character
    {
        chary[i] = ch; //Set read-in value to counter's position within array
        i = i + 1; //Increment your counter
        infile.get(ch); //Now get your next position within array
    } //Fall out of loop as soon as you hit a new line
    cout << "Length of first character array is: " << i << endl; //Display length to test
    cout << "Character read in is: " << ch << endl; //Display character to test
                                    //When I run it, this ch is blank

    //Convert the read-in character number to an integer number
    //Store the number in array: num1ary
    num1ary[i] = ch - 0;  //Convert position i in num1 array from char type to int type
    cout << "Number converted from char type to int type is: "
         <<num1ary[i]  << endl;  //Display num1 array position to test
                               //When I run it, numary1[i] is 10 

[vin]

When you fall out of this loop, ch = '\n'.

    while ( ch != '\n')  //While read-in value is not a new line character
    {
        chary[i] = ch; //Set read-in value to counter's position within array
        i = i + 1; //Increment your counter
        infile.get(ch); //Now get your next position within array
    } //Fall out of loop as soon as you hit a new line 

In this next line instead of ch, try chary[0].

    cout << "Character read in is: " << ch << endl; //Display character to test
                                    //When I run it, this ch is blank 

Not sure what your teacher means by subtract a 0 but probably subtract the ASCII value for '0'.

[georgep]

I had a very similar problem recently. I think you need to do this:

num1ary[i] = ch - '0'; //Convert position i in num1 array from char type to int type

[ErinCorona]

The teacher DID say to subtract the ASCII value from the number, but when I did that I got -38. So then I tried just subtracting the integer zero and that's what got me the answer 10. I'll go back and change a few lines and see what happens...Thanks for your input.

[ErinCorona]

Still not working...strange, because it seems to be reading the first two numbers backwards. Why? How? Here's the new code, with the above mentioned change...and below it I placed the output....What the program SHOULD be telling me is that the first number is 1 character long, and that character is 8. The second number on the second line is 3, so I'm not sure how it's going there first...Please help!

#include <iostream>    //Header files
#include <fstream>
#include <cmath>

using namespace std;

//File descriptors
ifstream infile;
ofstream outfile;

//Prototypes

int main()
{
    infile.open("BigNumbersV2.txt"); //Open text file to read from
    outfile.open("answers.out");    //Open textfile to write to
    if (!infile) //If input file did not open correctly
    {
        cout << "Error opening input file." << endl; //Display error message
        return 0; //Quit
    }
    if (!outfile) //If outfile does not open
    {
        cout << "Error opening output file." << endl; //Display error message
        return 0;  //Quit
    }
    int chary[25];   //Declare array for reading in numbers by character
    int num1ary[25]; //Declare array for storing number 1
    int num2ary[25]; //Declare array for storing number 2
    int sumary[25];  //Declare array for storing sum
    int i = 0;  //Declare and initialize an array position holder
    char ch;    //Declare variable for reading in each character from infile

    //Read-in the number
    infile.get(ch) >> chary[i]; //Read in first character
    cout << chary[i] << endl;   //Display position in the array to test
    outfile << chary[i] << endl;//Echo
    while ( ch != '\n')  //While read-in value is not a new line character
    {
        cout << ch << endl; //Display number grabbed to test
        outfile << ch << endl; //Echo
        i = i + 1; //Increment your counter
        cout << "Length of first character array is: " << i << endl; //Display length to test
        cout << "Character read in is: " << num1ary[i] << endl; //Display character to test
        outfile << "Length of first character array is: " << i << endl; //Echo
        outfile << "Character read in is: " << num1ary[i] << endl; //Echo
        infile.get(ch) >> chary[i]; //Now get your next position within array
    } //Fall out of loop as soon as you hit a new line

    //Convert the read-in character number to an integer number
    //Store the number in array: num1ary
    num1ary[i] = ch - '0';  //Convert position i in num1 array from char type to int type
    cout << "Number converted from char type to int type is: "
         <<num1ary[i]  << endl;  //Display num1 array position to test
    outfile << "Number converted from char type to int type is: " //Echo
            <<num1ary[i]  << endl;  //Echo   

3
8
Length of first character array is: 1
Character read in is: -1
Number converted from char type to int type is: -38

Just for clarity, this is the infile I'm reading from...

8
3
36123
85321
3862663
67426
2222222222222222222222222
7777777777777777777777777
9999999999999999999999999
9999999999999999999999999
4444444444444444444444444
999999999999999

[ErinCorona]

For future reference (for myself, really) it wasn't working because my array 'chary' was declared as an int, not a char array. Changing that fixed it. Go me. :)