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can we ask a user to input the size of array plz tell how with help of code ??????

+4 votes
asked Jul 6, 2022 by AADI JAIN (350 points)
int main()

int arr[n],


can we do this ?????

1 Answer

+2 votes
answered Jul 6, 2022 by Peter Minarik (77,930 points)
edited Jul 6, 2022 by Peter Minarik

Only if you input n first, then declare your array later.

In your code, you declare your arr to be n element long. However, at the time of execution at that point, the value of n is undefined. Hence the result is undetermined and your code is wrong.

Would you input the value of n first, the program would have arr initialized to the right size.

Here's an example code below:

#include <iostream>

using namespace std;

int main()
    size_t size;
    cout << "Please, enter the size of the array: ";
    cin >> size;
    int array[size];
    // Have fun using your array
    cout << "The actual size of array is: " << (sizeof(array) / sizeof(array[0])) << endl;
    return 0;
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