using a switch statement

here is my code. Here is a quick review of what i need to do: open a file of a list of numbers and get the first number and tally it for that number. Ex. number is 4563 it tallys 1 for number 4. And 2983 it tallys 1 for number 2. and loops through whole list and tallys numbers 1 - 9 and records them in the output. This outputs what i say but it outputs 0's for 1-9 instead of how many times it found a number that started with 1 and etc through 9.

Code:

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#include <fstream>
#include <iostream>
#include <string>

using namespace std;

int getFirstDigit(int num);


int main ()
{
       
        ifstream inFile;
        int number;
        int num1=0, num2=0, num3=0, num4=0, num5=0, num6=0, num7=0, num8=0, num9=0;
        string num11;
        int totals[10]={0,0,0,0,0,0,0,0,0,0};
        cout << "Enter 1 for librarybooks or Enter 2 for livejournal : ";
        cin >> number;

        if ( number == 1 )
        {
                inFile.open("librarybooks-1.txt");

                switch(num11[0])
                {
                        case '0' : totals[0]++;
                                break;
                        case '1' : totals[1]++;
                                break;
                        case'2' : totals[2]++;
                                break;
                        case'3' : totals[3]++;
                                break;
                        case'4' : totals[4]++;
                                break;
                        case'5' : totals[5]++;
                                break;
                        case'6' : totals[6]++;
                                break;
                        case'7' : totals[7]++;
                                break;
                        case'8' : totals[8]++;
                                break;
                        case'9' : totals[9]++;
                                break;
                }
       
       
                for (int i=1; i < 10; ++i)
                {
                        cout << "Number of " << i << "s : " << totals[i] << endl;
                }
        }

        else if ( number == 2 )
        {
               
        inFile.open("livejournal-1.txt");

        switch(num11[0])
                {
                        case '0' : totals[0]++;
                                break;
                        case '1' : totals[1]++;
                                break;
                        case'2' : totals[2]++;
                                break;
                        case'3' : totals[3]++;
                                break;
                        case'4' : totals[4]++;
                                break;
                        case'5' : totals[5]++;
                                break;
                        case'6' : totals[6]++;
                                break;
                        case'7' : totals[7]++;
                                break;
                        case'8' : totals[8]++;
                                break;
                        case'9' : totals[9]++;
                                break;
                }
       
       
                for (int i=1; i < 10; ++i)
                {
                        cout << "Number of " << i << "s : " << totals[i] << endl;
                }
        }

        else
                cout << "\n" << "Invalid number" << "\n" << endl;

       
        return 0;
}

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Code:

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                inFile.open("librarybooks-1.txt");

                switch(num11[0])

---

you are lucky that this does not crashed
you are opening the file, but where do you read info from it? your num11 string is always empty

Code:

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int totals[10]={0,0,0,0,0,0,0,0,0,0};

---

That's the same as

Code:

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int totals[10] = {};

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because any non-specified elements get initialized to zero. (In C, you need to use {0}, but in C++, {} works.)

Code:

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for (int i=1; i < 10; ++i)

---

I think you want to start at 0, not 1.

Code:

---

case'7' :

---

Unusual spacing, to be sure. :)

Since your code for number==1 and number==2 is the same except for which file you open, why not wrap only the file opening code in an if/else construct, and have everything else right in main()?

Code:

---

        if ( number == 1 )
        {
                inFile.open("librarybooks-1.txt");
        }
        else if ( number == 2 ) {
                inFile.open("livejournal-1.txt");
        }

        switch(num11[0])
        {
                case '0' : totals[0]++;
                        break;

        // ...

---

Your whole switch statement can be simplified into a single line:

Code:

---

++totals[num11[0]-'0'];

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Actually, a better translation would be:

Code:

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#include <ctype.h>
if(isdigit(num11[0])) {
    ++totals[num11[0]-'0'];
}

---

since, once num11 is actually read from the file, the file probably contains stuff other than digits . . . .

Quote:

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Originally Posted by dwks

Code:

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        if ( number == 1 )
        {
                inFile.open("librarybooks-1.txt");
        }
        else if ( number == 2 ) {
                inFile.open("livejournal-1.txt");
        }

        switch(num11[0])
        {
                case '0' : totals[0]++;
                        break;

        // ...

---

---

Quote:

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Originally Posted by h_howee

Your whole switch statement can be simplified into a single line:

Code:

---

++totals[num11[0]-'0'];

---

---

thanks. I have used both those ideas which has shortened my code. My output for each number is still 0 for each number 1-9 instead of the tallied number it came up with.

Well, do you have something like this?

Code:

---

inFile >> num11;

---

for a word, or

Code:

---

getline(inFile, num11);

---

for a whole line.

As it stands, your num11 is never set.

Quote:

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Originally Posted by dwks

Actually, a better translation would be:

Code:

---

#include <ctype.h>
if(isdigit(num11[0])) {
    ++totals[num11[0]-'0'];
}

---

since, once num11 is actually read from the file, the file probably contains stuff other than digits . . . .

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yes it does...first 2 lines are words

Quote:

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Originally Posted by dwks

Well, do you have something like this?

Code:

---

inFile >> num11;

---

for a word, or

Code:

---

getline(inFile, num11);

---

for a whole line.

As it stands, your num11 is never set.

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im new to this...how do i set it? also, since i am using a switch someone had helped me previously with this and used an array. i think i might have some stuff in there containing both but i need to get rid of and just use a switch if this makes any sense.

What dwks means is that you define the std::string num11, but you never use it, so it's going to end up empty no matter what you do.

yea i had to code working perfect until i realized I had to put something in to ask the user to pick out of 2 files for this program to loop through. For that i used an if else statement and now i can't seem to get it to work. It just outputs 0's instead of the numbers like it did when i had it.

Quote:

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Originally Posted by dukebdx12

i used an if else statement and now i can't seem to get it to work. It just outputs 0's instead of the numbers like it did when i had it.

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can you post your updated code?

You're doing something like this.

Code:

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string str;
ifstream file("whatever.txt");

if(str == "") {
    cout << "why is str empty???\n";
}

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Opening the file is a completely independent operation from looking at the contents of the string. Opening a file does not magically "tie" a string to the file, thus putting the contents of the file in the string. You have to do that yourself.

Code:

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string str;
ifstream file("whatever.txt");

file >> str;

if(str != "") {
    cout << "Aha! The string is no longer empty . . . .\n";
}

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