How do I change the size of an array and fill it with automated elements?

Question

I have an array with set elements 1 - 10. I have decided the size of the array and I have decided the elements of the array. My question is, how do I create an array of size x and fill it with elements 1,2,3,4 . . .

//sets values of the array elements and print them.
cout << "Array should contain x integers set to 1,2,3" << endl;

// QUESTION: How can I change the size of the array and have
//           have values automatically entered?
int array[] = { 1,2,3,4,5,6,7,8,9,10 };
for (int i = 0; i <= (sizeof(array) / sizeof(int)-1); ++i) {

    // sizeof(array)/sizeof(int) = 36/4. ints are 4.
    cout << "Element " << i << " = " << array[i] << endl;
}
    cout << "The number of elements in the array is: "  
    << sizeof(array) / sizeof(int) << endl;
    cout << endl;
    cout << endl;

You need a dynamic array, right? I think this http://stackoverflow.com/questions/4029870/how-to-create-a-dynamic-array-of-integers can be useful. — Drimades Boy, Apr 01 '17 at 06:41
`int array[x]; std::iota( std::begin(array), std::end(array), 1 );` — M.M, Apr 01 '17 at 06:53
A comparison in a for-loop is usually `!=` or `<`. That saves you from compensating for `<=` with a `-1`. — Bo Persson, Apr 01 '17 at 08:33

score 1 · Answer 1 · answered Apr 01 '17 at 06:58

you can use dynamic memory allocation approach for your array, there you can give as much size as you want. Thanks.

//Variable size of Array program to print Array elements

#include <iostream>
using namespace std;

int main()
{
    cout << "Enter Array size x:" << endl;
    int x = 0;
    cin >> x;

    int *ptrArray = new int[x];

    //Inittialise Array 
    for (int i = 0; i < x; i++)
    {
        ptrArray[i] = i + 1;
    }

    //Print Array elemts
    cout << "Array elements:";
    for (int i = 0; i < x; i++)
    {
        cout << ptrArray[i] << endl;
    }   

    delete[] ptrArray;

    return 0;
}

Awesome answer! Thank you! – Jim Sartor Apr 01 '17 at 08:36 — Jim Sartor, Apr 01 '17 at 08:36

How do I change the size of an array and fill it with automated elements?

1 Answers1