How does fill accept an array multiplied by a long long?

Question

C++ / C#

Given this code:

#include  <iostream>
#include <algorithm>

using namespace std;
int main() {
    long long n;
    cin >> n;
    int a[1000000];
    fill(a, a+n, 1);
    return 0;
}

Why does fill() take a value like array+long long? (2nd argument)

Answer 1

Pointer Arithmetic . This results in a pointer to the last element of the array, like ::end() for collections.