a=int(input())
b=int(input())
c=int(input())
if a==b:
  print(a)
  exit(0)
if b==c:
  print(b)
  exit(0)
if (a==c):
  print(a)
  exit(0)
if a>b and a<c or a<b and a>c:
  print(a)
  exit(0)
if b>a and b<c or b<a and b>c:
  print(b)
  exit(0)
if c>a and c<b or c<a and c>b:
  print(c)
  exit(0)