Consider N disks in the plane: C1, C2, ..., CN such that, for all i, where 0 < i < N, we have the center of Ci on the circumference of Ci+1, and the center of Cn on the circumference of C1. What is the maximum number of pairs of disks (Ci, Cj ), with 1 ≤ i, j ≤ N such that Ci properly contains Cj . Note, the set T properly contains, the set S, if and only if S ⊆ T and S ̸= T. Input A number of inputs (< 1000) with integer N (1 ≤ N ≤ 1000000). Output Output one line per input, the answer. Sample Input 1 2 3 Sample Output 0 0 1