Read input, return values

[amatoo04]

hi guys, i am trying to finish up a program i started this morning and basically i got the whole input and output down... i just need help with the function which will scan the file and return number of lines, amount of characters, and amount of alphabetical characters. I was wondering if i would need 3 different functions, and how would i go about setting those up.

here is my code so far

/*Write a program, which scans a file and counts the number of characters, the number of lines, and the number 
of alphabetic characters in the file.Have main() open the file and pass the file pointer to a function named count. 
Count passes back the number of characters and the number of alphabetic characters.  main() prints the answers and closes the file.
 
*/
 
#include<iostream>
#include<fstream>
using namespace std;
 
 
 
char countline(char c);
void valuefile(ifstream & in, ofstream & out);
 
int main (){
 
    ifstream in;
    ofstream out;
    char inName[100];
    char outName[100];
 
    do{
        cout << "Enter name of plain text file:\n";
        cin >> inName;
        in.open(inName);
        if(!in.is_open()){
            cerr << "Failed to open " << inName << " - Now exiting\n";
            exit(-1);
        }
    }while(!in.is_open());
do{
    cout << "Enter name for output file:\n";
    cin >> outName;
    out.open(outName);
    if(!out.is_open()){
        cerr << "Failed to open " << outName << " - Now exiting\n";
            exit(-1);
    }
}while (!out.is_open());{
valuefile(in,out);
cout << "Output file is in " << outName << endl;
}
return 0;
}
 
 
 
char countline( char c){
 
    if (c == ' ' )
        return c + 1;    // gives me a ! instead of adding amount of spaces
    else 
        return c;
}
void valuefile(ifstream & in, ofstream & out){
    while( !in.eof()){
        char c = in.get();
        out << countline(c);
 
    }
} 

any input would help, thanks guys

[DeMan]

I would suggest three functions for code clarity, although because everything is related some people would advise to do it all cocurrently. To do this you would either need to be comfortable passing out pointers or give the results in an array or structure of some sort. I will assume the first, and outline the basic steps....

Depending on definition, counting lines can mean many things, I would advise you count end of line characters (looking for '\n' might work, but I think there is another value to represent end of line in this sort of context (though i can't think what it might be)) until you reach end of file (eof I think)
Your countline method returns ! because you are adding 1 to the character ' ' (which I don't think is what you want to do, that is, you are bumping the character forward)

Number of characters can also be done trivially using a while not eol loop, and simply count the characters. (Depending on what you are actually doing you might like to 'cheat' here. 1 character = 1 byte, so if you look at the file size it should be pretty close to the number of characters).

Number of of alphabetic characters is alslo reasonably easy. Implement a method that returns whether a character is alphabetical or not and count how many return true when you pass the characters from the file in. Basically, beacuse characters are numeric values, you can do normal logic on them as you would with numbers. You need to make sure that they are in one of the ranges 'a' to 'z' or 'A' to 'Z'
ie: if(thischar>'a'||thischar<'z'...etc);
you could also implement this as a switch statement eg:

switch(thischar)
{
case 'a': case'b': case 'c'......
return true;
default:
return false
}
 

[DeMan]

I just reread my post, and think that for the most part, the tasks are trivial enough to be all in one place, though you might like to implement the isAlpha function. Then you can count lines, characters and alphabetic characters at the same time. (I have assumed above also, that when you want to count characters you want to count invisible ones too)

[amatoo04]

ok thanks for that response. my only problem now is programming the code to actually count these things, the way i keep trying it just changes the value to the next character.

[DeMan]

remove the method countline, and move the ifs into your main code wherever the method is currently read, then set up
in counter=0; (or similar) at the top of your program and increment that inside your if....

if(c=' ')
{
  counter++;
}