Problem:
Remainder of Big Integers

Given two integers $A$ and $B$, compute the remainder of $\frac{A}{B}$.

Input

Two integers $A$ and $B$ separated by a space character are given in a line.

Output

Print the remainder in a line.

Constraints

$0 \leq A, B \leq 10^{1000}$

$B \ne 0$

Sample Input 1

5 8

Sample Output 1

5

Sample Input 2

100 25

Sample Output 2

0

Solution in Ruby (judge verdict: Accepted)

require "bigdecimal"
a, b = gets.split.map { |x| BigDecimal(x) }
puts (a % b).floor