''' for i in range(99999): n = int(input()) if n!=0: print(n) else: break ''' ''' n = input() n = int(n) for i in range(10000): while n!=0: print(n) n = n-1 ''' ''' n = input() n = int(n) for i in range(0, n+1): print(i) ''' ''' n = input() n = int(n) s = 0 for i in range(1, n+1): if i%2==0: s += i print(s) '''