[ambition]

That's disingenuous. When they say "no built-in functions", they really only mean "don't use a library function that makes this task trivial." Which eliminates 'strlen' in C, 'length' in Haskell, 'len' in Python, etc.

[th0ma5]

sort of trivial in python with just statements: i=0 for x in thestring i+=1 print i