Дан массив целых случайных чисел и Обработка строк

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#include "iostream"
#include "ctime"
using namespace std;
 
int main(int argc, char* argv[])
{
    setlocale(LC_ALL, "Russian");
    srand(time(NULL));
    unsigned int arrSize;
    int *arr;
    int sum = 0;
    do
    {
        cout << "Введите размер массива (3-20): ";
        cin >> arrSize;
    } while (arrSize<3 || arrSize>20);
    arr = new int [arrSize];
    for (int i=0; i<arrSize; i++)
    {
        arr[i] = -10 + rand() % 21;     // -10 .. +10
        cout << arr[i] << " ";
        if (arr[i]<0) sum=sum+arr[i];
    }
    delete [] arr;
    cout << endl;
    cout << "Сумма отрицатеьных чисел: " << sum << endl;
    return 0;
}