input: Write a python function to check if two strings are anagrams.
  assert is_anagram("listen", "silent") == 1
  assert is_anagram("hello", "billion") == 0
  assert is_anagram("triangle", "integral") == 1
output: def is_anagram(s1, s2):
      return 1 if sorted(s1) == sorted(s2) else 0