C++编程：汉诺塔C++代码解析

#include <iostream> 
#include <stdlib.h>
using namespace std;
void Move(int n, char A, char B, char C)
{
    if (n == 1)
    {
        cout << "Move disk " << n << " from " << A << " to " << C << endl;
    }
    else
    {
        Move(n - 1, A, C, B);
        cout << "Move disk " << n << " from " << A << " to " << C << endl;
        Move(n - 1, B, A, C);
    }
}
void Hanoi(int n)
{
    if (n <= 0)
        return;
    Move(n, 'A', 'B', 'C');
} 
int main()
{
  int x;
  cin >> x;
    Hanoi(x);
    int f[1000]={0,1};
    for(int i=2;i<=x;i++)
        f[i]=2*f[i-1]+1;
    cout<<f[x]<<endl;
    system("pause");
    return 0;
}

请问：main函数里的f【x】数组以及for循环是什么意思？

求出总数