import math
proc getchar_unlocked():char {. importc:"getchar_unlocked",header: "<stdio.h>" .}
proc scan(): int =
  while true:
    var k = getchar_unlocked()
    if k < '0' or k > '9': break
    else: result = 10 * result + k.ord - '0'.ord

# 15 35 => 50 15*35
# 5*(3 7 =>)
let a = scan()
let b = scan()
let g = a.gcd(b)
echo g
# echo (a+b).gcd(a*b)