import math
arr = list(map(int, input().split()))
n = len(arr)
ans = arr[0]
for x in arr[1:]:
ans = math.gcd(ans, x)
print(ans)
aW1wb3J0IG1hdGgKYXJyID0gbGlzdChtYXAoaW50LCBpbnB1dCgpLnNwbGl0KCkpKQpuID0gbGVuKGFycikKYW5zID0gYXJyWzBdCmZvciB4IGluIGFyclsxOl06CglhbnMgPSBtYXRoLmdjZChhbnMsIHgpCnByaW50KGFucyk=