dynamic management of the memory.

[puretnaant]

Hi, Im trying to run this program using dynamic memory i cant seem to get it to keep running it crashes on me.

I have the working program so the code is correct im just haveing trouble trying to convert it correctly.

Thank You,

#include <iostream>
#include <fstream>
using namespace std;

const int SIZE = 20;    


void getVector(int *&, int *&,  int);
int findIntersection(int [], int, int [], int, int *&, int);
void displayIntVector(int [], int);
void saveVector(int [], int);


int main(){
       int *A=NULL;
   int *B;
   int *C;
   int sizeA=0; 
   int sizeB=0; 
   int sizeC=0;


   getVector(A, sizeA, B, sizeB, SIZE);
   

   sizeC = findIntersection(A, sizeA, B, sizeB, C, SIZE);
   

   saveVector(C, sizeC);
   displayIntVector(C, sizeC);
   
   system("pause");
   return 0;
}


void getVector(int *&A, int *&B, int maxSize){
     
     ifstream fileA;
     fileA.open ("A.data");
     if(!fileA){cout<<"error: opening a.data\n"; system("pause"); exit(0);}
     fileA>>sizeA;
     if(sizeA>=maxSize){cout<<"error: Too much data in A.data"; exit(0);};
     cout<<"Reading data from a.data\n";
     for(int index = 0; index < sizeA; index++) fileA>> A [index];
     fileA.close();
     displayIntVector(A, sizeA);




     ifstream fileB;
     fileB.open ("B.data");
     if(!fileB){cout<<"error: opening a.data\n"; system("pause"); exit(0);}
     fileB>>sizeB;
     if(sizeB>=maxSize){cout<<"error: Too much data in A.data"; exit(0);};
     cout<<"Reading data from a.data\n";
     for(int index = 0; index < sizeB; index++) fileB>> B [index];
     fileA.close();
     displayIntVector(B, sizeB);

      
}



int findIntersection(int A[], int sizeA, int B[], int sizeB, int *&C, int size){
    
   int index3 = 0;  
   
   for(int index1 = 0; index1 < sizeA; index1++)
   
   for(int index2 = 0; index2 < sizeA; index2++)
   
   if(A[index1] == B[index2]) C[index3++] = A[index1];
           
           
           
    return index3;
    


}

void displayIntVector(int a[], int num){
     if(!num) cout<<"There are no elements.\n";
     else{
        for (int index = 0; index < num; index++) cout << a[index] <<" ";
      cout <<endl<< endl;
     
     }


}



void saveVector(int a[], int size){
   
     ofstream fileC;
     fileC.open("C.data");
     if(!fileC){cout<<"eror: opening c.data\n"; system("pause"); exit(0);}
     cout<<"Saving Intersection(A,B) in c.data\n";
     fileC<<size<<endl;
     for(int index = 0;  index < size; index++) fileC<<a[index]<<endl;
    fileC.close();
}

[daviddoria]

Where does the problem occur?

[puretnaant]

Im not shure thats what im haveing trouble with.

This is the original working code that im trying to convert using dynamic managemnt of memeory if it helps answer a question. Thats the toruble im haveing is trying to conver it.

#include <iostream>
#include <fstream>
using namespace std;

const int SIZE = 20;    // Maximum number of values in each array

// Function Prototypes
void getArrays(int [], int &, int [], int &, int);
int findIntersection(int [], int, int [], int, int [], int);
void displayIntArray(int [], int);
void saveArray(int [], int);


int main(){
      
   //Sets A ,B, C and the atual corresponding size 
   int setA[SIZE], setB[SIZE], setC[SIZE], sizeA=0, sizeB=0, sizeC=0;

   // Get values for the sets A and B from A.data and B.data.
   getArrays(setA, sizeA, setB, sizeB, SIZE);
   
   // Find the intersection of the two sets A and B
   sizeC = findIntersection(setA, sizeA, setB, sizeB, setC, SIZE);
   
   // Display setC (intersecting values of setA and setB) and save it in C.data
   saveArray(setC, sizeC);
   displayIntArray(setC, sizeC);
   
   system("pause");
   return 0;
}


void getArrays(int A[], int &sizeA, int B[], int &sizeB , int maxSize){
     
     ifstream fileA;
     fileA.open ("A.data");
     if(!fileA){cout<<"error: opening a.data\n"; system("pause"); exit(0);}
     fileA>>sizeA;
     if(sizeA>=maxSize){cout<<"error: Too much data in A.data"; exit(0);};
     cout<<"Reading data from a.data\n";
     for(int index = 0; index < sizeA; index++) fileA>> A [index];
     fileA.close();
     displayIntArray(A, sizeA);




     ifstream fileB;
     fileB.open ("B.data");
     if(!fileB){cout<<"error: opening a.data\n"; system("pause"); exit(0);}
     fileB>>sizeB;
     if(sizeB>=maxSize){cout<<"error: Too much data in A.data"; exit(0);};
     cout<<"Reading data from a.data\n";
     for(int index = 0; index < sizeB; index++) fileB>> B [index];
     fileA.close();
     displayIntArray(B, sizeB);

      
}


int findIntersection(int A[], int sizeA, int B[], int sizeB, int C[], int size){
    
   int index3 = 0;  
   
   for(int index1 = 0; index1 < sizeA; index1++)
   
   for(int index2 = 0; index2 < sizeA; index2++)
   
   if(A[index1] == B[index2]) C[index3++] = A[index1];
           
           
           
    return index3;
    
//TODO

}


void displayIntArray(int a[], int num){
     if(!num) cout<<"There are no elements.\n";
     else{
        for (int index = 0; index < num; index++) cout << a[index] <<" ";
      cout <<endl<< endl;
     
     }

//TODO

}


void saveArray(int a[], int size){
     
     ofstream fileC;
     fileC.open("C.data");
     if(!fileC){cout<<"eror: opening c.data\n"; system("pause"); exit(0);}
     cout<<"Saving Intersection(A,B) in c.data\n";
     fileC<<size<<endl;
     for(int index = 0;  index < size; index++) fileC<<a[index]<<endl;
    fileC.close();
}

[daviddoria]

That's what you said before... but WHERE/WHAT is the trouble? Are there compiler errors? Does it crash? etc.

[puretnaant]

I dont know were the trouble is. The compiler doesn't give me errors. When it runs the .exe it crashes.

[daviddoria]

You should step through the code with a debugger. If you don't want to do that, you should sprinkle output statements throughout the code. The goal is to figure out where the code is crashing.