def is_CPP(var):
if var[0] == '_' or var[-1] == '_':
return 0
for i, char in enumerate(var):
if char.isupper():
return 0
if i == 0:
continue
if var[i - 1] + char == '__':
return 0
return 1
def is_Java(var):
if var[0].isupper():
return 0
if '_' in var:
return 0
return 1
def CPP_to_Java(cpp):
java = ''
for i, char in enumerate(cpp):
if char == '_':
continue
if cpp[i - 1] == '_':
java += char.upper()
continue
java += char
return java
def Java_to_CPP(java):
cpp = ''
for char in java:
if char.isupper():
cpp += '_' + char.lower()
continue
cpp += char
return cpp
s = input()
if is_Java(s) and is_CPP(s):
print(s)
elif is_Java(s):
print(Java_to_CPP(s))
elif is_CPP(s):
print(CPP_to_Java(s))
else:
print('Error!')
