SP3871 GCDEX - GCD Extreme

Given the value of N, you will have to find the value of G. The meaning of G is given in the following code ``` G=0; for(i = 1 ; i < N ; i++) for(j = i+1 ; j

The input file contains at most 20000 lines of inputs. Each line contains an integer N (1 < N < 1000001). The meaning of N is given in the problem statement. Input is terminated by a line containing a single zero.

For each line of input produce one line of output. This line contains the value of G for the corresponding N. The value of G will fit in a 64-bit signed integer.