The fraction $m / n$ is called regular irreducible, if $0 < m < n$ and $GCD(m, n) = 1$. Find the number of regular irreducible fractions with the denominator $n$. \InputFile Each line is a separate test case that contains one integer $n~(n < 10^9)$. The last line contains $0$ and is not processed. The number of test cases is no more than $100$. \OutputFile For each value of $n$ print in a separate line the answer to the problem.