# Write a function that takes a string and a substring and
# removes the second instance of the substring from the string
# without using any built-in functions/methods besides len()
# (i.e. you may NOT use .index()).
# The substring will be at most three characters long.
#
# After completing the solution without using built-in functions/methods,
# rewrite a function to use built-in functions/methods.
# Then, compare both solutions.

def removeSecond(l, n):











print(removeSecond('bird', 'i'))       # bird
print(removeSecond('bird', 'x'))       # bird
print(removeSecond('ibiridi', 'i'))    # ibridi
print(removeSecond('kiaeb', 'iae'))    # kiaeb
print(removeSecond('kiaebiaeriaediae', 'iae'))    # kiaebriaediae
print(removeSecond('kiaebiariaediaeia', 'iae'))   # kiaebiardiaeia