trouble using fstream with arrays

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Views: 262 | Replies: 3

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Join Date: Jul 2008

Posts: 11

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greyghost86 greyghost86 is offline

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trouble using fstream with arrays

Jul 19th, 2008

In the code below i can'f figure out how to get the numbers from my inFile that will be reversed then put into my outFile. I left part of the code unfinished. not sure what I am supposed to put in between >> >>. pretty lost on this one. Im new at this so go easy. Thanks

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  [icode]
#include <iostream>
#include <string>
#include <fstream>
 
using namespace std;
std::string word[5];
 
int main ()
{
	//Declaring Variables
ifstream inFile;
ifstream inFile1;
ofstream outFile;
 
int item[5]; // An array item of 5 components
int counter;
int num, num1, num2, num3, num4;
 
 
inFile.open("numbers.txt");
inFile1.open("words.txt");
outFile.open("numberout.txt");
 
 
 
for (counter = 0; counter < 5; counter++)
{
inFile >> num >> num1 >> num2 >> num3 >> num4;
}
 
for (counter = 5; counter >= 0; counter--)
{
// unfinished code
outFile <<  << endl;
}
[/icode]
 [icode]
#include <iostream>
#include <string>
#include <fstream>

using namespace std;
std::string word[5];

int main ()
{
	//Declaring Variables
ifstream inFile;
ifstream inFile1;
ofstream outFile;

int item[5]; // An array item of 5 components
int counter;
int num, num1, num2, num3, num4;


inFile.open("numbers.txt");
inFile1.open("words.txt");
outFile.open("numberout.txt");



for (counter = 0; counter < 5; counter++)
{
inFile >> num >> num1 >> num2 >> num3 >> num4;
}

for (counter = 5; counter >= 0; counter--)
{
// unfinished code
outFile <<  << endl;
}
[/icode]

Last edited by greyghost86 : Jul 19th, 2008 at 6:25 pm.

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Join Date: Oct 2007

Location: Cherry Hill, NJ

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Duoas

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Re: trouble using fstream with arrays

Jul 19th, 2008

You need to rethink why you are using a loop.
Ideally, if you have to do things multiple times, it suggests a loop and/or an array.

Since you need to remember five numbers, instead of writing:
int num, num1, num2, ...

you can instead just use an array:
int items[ 5 ];

I would have named it "numbers":
int numbers[ 5 ];
(But I'll still use "items" below.)

Now below, you want to read 5 numbers (and remember them). You've got a nice loop there that counts from 0 to 4, and a nice array, so let's put them together:

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for (counter = 0; counter < 5; counter++)
  {
  cin >> items[ counter ];
  }
for (counter = 0; counter < 5; counter++)
  {
  cin >> items[ counter ];
  }

You've already got a nice loop there that counts from 5 to 0. You'll have to fix that five to the proper number to start at. (Remember, arrays are index from 0 to N-1, where N is the number of elements in the array.) And I think you should know by now what goes inside the loop.

Hope this helps.

Last edited by Duoas : Jul 19th, 2008 at 6:32 pm.