Python:
day = int(input())
if 1 <= day <= 10:
print('1')
elif 11 <= day <= 20:
print('2')
elif 21 <= day <= 31:
print('3')
Объяснение:
Python:
day = int(input())
if 1 <= day <= 10:
print('1')
elif 11 <= day <= 20:
print('2')
elif 21 <= day <= 31:
print('3')
Объяснение: