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Program keeps crashing after i give 2 inputs!!!

wildcharizard (4)
Hi I need help on my program that keeps crashing exactly after two inputs.. ive been stuck on this for really long and idk whats wrong :(

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/*
Write a program containing the following functions, in this order:
main - calls the other functions; otherwise does almost nothing
getSize - which asks the user how many strings they want
getSpace - which gets an array in the heap of the size requested by the user
inputData - which allows the user to input the strings and stores them
in the array
printData - which prints all the strings, one string per line
destroy - which returns all the space to the heap

All of these functions, except main, shall have a return type of void.
*/



#include <iostream>
#include <string>

using namespace std;

void getSize (int *numStrings);
void getSpace (int *numStrings, string newArray[]);
void inputData (int *numStrings, string newArray[]);

/* Calls the other functions; otherwise does almost nothing */

int main ()
{
    int numStrings;

    string newArray;

    getSize (&numStrings);

    getSpace (&numStrings, &newArray);

    inputData (&numStrings, &newArray);

    return 0;
}

/*getSize - which asks the user how many strings they want */
void getSize (int *numStrings)
{
    cout << "How many strings would you like? " << endl;
    cin >> *numStrings;
}

/*getSpace - which gets an array in the heap of the size requested by the user */
void getSpace (int *numStrings, string newArray[] )
{
    newArray = new string [*numStrings];
}

/* inputData - which allows the user to input the strings and stores them */
void inputData (int *numStrings, string newArray[])
{
    string data;
    for (int i = 0; i < *numStrings; i++)
    {
        cout << "Please enter string #" << i << endl;
        cin >> data;
        newArray[i] = data;
        cout << newArray[i] << endl;
    }
}
Last edited on
MiiNiPaa (8886)
string newArray; Lies. newArray is not an array. It is a single variable of type string.

newArray = new string [*numStrings]; You are modifying pointer value. Which is local to function. No changes would be visible outside it. Also there is a memory leak.

inputData (&numStrings, &newArray);
You are passing pointer to single variable. newArray[0] evaluates exactly to that single variable, but newArray[1] (second string entered) is some random memory and behavior is undefined.

This is why pointers are bad, folk.
Last edited on
wildcharizard (4)
How would i fix this??
Sorry im new to pointers and functions in general..
Ive been trying a bunch of other methods but i still cant get it right.

What is the correct way to write functions getSpace? I dont understand how to create an array in a void function and pass it back to main like the assignment asks.. From what I know c++ functions cant return them
Last edited on
MiiNiPaa (8886)
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string* newArray; //Declares pointer to array

string*getSpace (int numStrings); //Make function return allocated buffer
//Make changes to function yourself

newArray = getSpace(num); //Assign buffer returned from function to your array pointer.
wildcharizard (4)
Thank you so much for you help!!
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