text = input().lower().split()
for i in range(len(text)):
for j in range(len(text)):
if (j + len(text[max(0, i - 1)])) % 2 == 0:
text = text[:j] + text[j].upper() + text[j+1:]
print(*text)
def convert(s):
r, i = '', 0
for c in s:
if c.isalpha():
r += [str.upper, str.lower](c)
i = (i + 1) % 2
else: r += c
return r
print(convert(input())) А можно сократить до такого: def convert(s, upper = True):
return ''.join([str.upper, str.lower][upper := upper != c.isalpha()](c) for c in s)