#include <iostream>
int *MultiplyByTwo(int arr[], int size){
for (int i = 0; i < size; i++) {
arr[i] *= 2;
}
return arr;
}
int main() {
int arr[] = {1, 2, 3, 4, 5};
int size = sizeof arr/sizeof arr[0];
int *p = MultiplyByTwo(arr, size);
for (int i = 0; i < size; ++i) {
std::cout << p[i] << " ";
}
return 0;
}
/*
run:
2 4 6 8 10
*/