import string
def only_digit_letters(s):
for ch in s:
if ch not in string.digits:
return False
return True
s = "92823"
if only_digit_letters(s):
print ("yes");
else:
print ("no");
s = "92 82 3"
if only_digit_letters(s):
print ("yes");
else:
print ("no");
s = "3.14"
if only_digit_letters(s):
print ("yes");
else:
print ("no");
'''
run:
yes
no
no
'''