Hi everyone,
I generate in a for loop:
1- An array made of random numbers
2- Add the elements of the array and store the
result in a number S
3- finally write in a .txt file the
number j(number of time that the for-loop has been executed)
and the number S for each j like this:
j=0 S=x
j=1 S=x
j=2 S=x
Steps 1 and 2 work fine.
Does someone has an idea how I can write
the js and the number S in a .txt file?
here is how my code till now looks like:

#include <stdlib.h>
#include <time.h>
#include <iostream>

using namespace std;

// The function RandomNum creates random numbers
// in the range between small and big

void RandomNum(double small,double big ,int p, double *array)   
{                                         
     double range=(big-small)+1;  
    for (int i=0; i<p; i++){
   array[i]=small+int(range*rand()/(RAND_MAX + 1.0)); 
	}
}

//the function AdditionArr Add the elements of an 
//array and store the result in a number S

double AdditionArr (double *Arr,int k)  
{
      int i; 
      double Sum=0.0;
	  for (i=0; i<k; i++){
	   Sum+=Arr[i];
	    }
  return Sum;      
}

int main()
	{
srand((unsigned)time(0));
int  p=3;
int j;		
double S,array[3];
        for(j=0;j<3;j++){
        RandomNum(-1.5,1.5 ,p,&array[0]);
       S=AdditionArr (&array[0],p);
	for (int k=0; k<p; k++){
	cout << "array"<<"["<< k << "]" <<" = " << array[k] << endl;
			   	  }
	cout << "S=" << S << endl;
	cout << endl;
		}
        return 0;
	}

Thank you

1st u need to include fstream that is #include <fstream> ,

and then declare ur input and output streams ifstream in_file; , ofstream out-file; only if u gona use both of them and again u need to open them
using in_file.open("Info.txt") that is u need to name ur txt file whichever name u want.... the in_file reads the input from the text file.... and the out file write the output to the text file and u also needs to open it out_file.open("Info.txt") and if u want to write U will have something like out_file << "Write Whatever" << endl; and if u want to read is the same thing in_file >> num; ..... On in_file if u wana write something u use cout << "Write whatever" << endl; its unlike out_file where u use the variable which u have declared such as out_file

at the end u need to close them out_data.close();, in_file.close();

1st u need to include fstream that is #include <fstream> ,

and then declare ur input and output streams ifstream in_file; , ofstream out-file; only if u gona use both of them and again u need to open them
using in_file.open("Info.txt") that is u need to name ur txt file whichever name u want.... the in_file reads the input from the text file.... and the out file write the output to the text file and u also needs to open it out_file.open("Info.txt") and if u want to write U will have something like out_file << "Write Whatever" << endl; and if u want to read is the same thing in_file >> num; ..... On in_file if u wana write something u use cout << "Write whatever" << endl; its unlike out_file where u use the variable which u have declared such as out_file

at the end u need to close them out_data.close();, in_file.close();

Thank you for the hint:cool:

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