Find letters from a text file

Question

So I am new to c++ and i am having trouble with a program. I am trying to search through a file and then find the first occurrence of all 26 upper case letters(A,B,C...) as well as lower case letters (a,b,c,d...). I have been working with a code and figured it would be easiest to take the file and create it into a vector then go through the vector and find the first instance of each letter. Here is a example of my code.

int main()
{
    int i;
    string file = input; // User inputted file
    vector<string> v;
    ifstream ist{ file };
    if (!ist)
        error("Can not open inputed file ", file);
    while (!ist.eof())
    {
        string x;
        ist >> x;
        v.push_back(x); // Creates a string vector that is filled with everything
        // in the file
    }
    // Find A in text.
    vector<int> location;
    location = find(v.begin(), v.end(), 'A');
    if (location != v.end())
        cout << "Found A at location " << location;
    else
cout << "A was not found"

I was able to successfully retrieve the vector v and it was filled with what the file had inside. The area of trouble is how is it possible to get the location of the letter from the string vector. I am still need to c++ so i could be approaching the problem all wrong. If you could help me out that would be awesome. Thanks.

The right tool to solve such problems is your debugger. You should step through your code line-by-line *before* asking on Stack Overflow. For more help, please read [How to debug small programs (by Eric Lippert)](https://ericlippert.com/2014/03/05/how-to-debug-small-programs/). At a minimum, you should \[edit] your question to include a [Minimal, Complete, and Verifiable](http://stackoverflow.com/help/mcve) example that reproduces your problem, along with the observations you made in the debugger. — πάντα ῥεῖ, Oct 18 '16 at 00:40
@πάνταῥεῖ: The right tool here is a good introductory [book](http://stackoverflow.com/q/388242/1889329). If you write `vector` to mean *"sequence of characters"*, you really need to get the basics straight. A debugger isn't going to help at this point. — IInspectable, Oct 18 '16 at 00:45
On topic: why bother with the vector? Why not read the file character by character and stop reading the file as soon as you find the required character? Off topic: `while (!ist.eof())` is a common mistake. [Read more about it here.](http://stackoverflow.com/questions/5605125/why-is-iostreameof-inside-a-loop-condition-considered-wrong) — user4581301, Oct 18 '16 at 00:54
@user4581301 So are you saying while in the while loop look for the each character? how would i go about doing that? Should it be a if statement? — ConCon19, Oct 18 '16 at 01:07
Suggestion: Write down what you want to do in the order you want to do it. Start walking through it on paper step by step with a small data set. Does it make sense? If so, turn it into code. — user4581301, Oct 18 '16 at 03:07

score 0 · Answer 1 · answered Oct 18 '16 at 00:48

0

Your vector v contains all strings from file, while you are searching for letter.

make v vector<char> and read by one character

answered Oct 18 '16 at 00:48

Вячеслав

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Find letters from a text file

1 Answers1