Solutions to strings HW06:

#-----------------------
def countLetter(text, letter):
    count = 0
    for i in range(len(text)):
        if text[i] == letter:
            count += 1
    return count


#-----------------------
def findLetter(A, B):
    for i in range(len(A)):
        if A[i] == B: #If found character
            return i  #Immediately done
    #If we finished loop w/o returning,
    #then B wasn't in the string
    return -1

#-----------------------
def backwards(A):
    s = ""
    for i in range(len(A)-1, -1, -1): #loops from: len()-1, down to 0, (excluding -1)
        s += A[i]
    return s

#-----------------------
def emphasize(text):
    s = ""
    for i in range(len(text)):
        if text[i] == ".":
            s += "!"
        else:
            s += text[i]
    return s


#-----------------------
# Three ways to write isVowel

def isVowel(c):
    isLowerV =  (c == "a" or c == "e" or c == "i" or c == "o" or c == "u" or c == "y")
    isUpperV =  (c == "A" or c == "E" or c == "I" or c == "O" or c == "U" or c == "Y")
    return isLowerV or isUpperV  #could also do it all in one long line, but I like splitting it

def isVowel2(c): #Less repetitive
    vowels = "AEIOUYaeiouy"
    for i in range(len(vowels)):
        if vowels[i] == c:
            return True
    return False

def isVowel3(c): # Least repetitive, use findletter to do same check
    return findLetter("AEIOUYaeiouy", c) != -1

#-----------------------
# Note: this is an excellent place to re-use the isVowel helper function
# It's both easier to write, and easier to read/understand your own code

def justTheVowels(text):
    s = ""
    for i in range(len(text)):
        if isVowel(text[i]):
            s += text[i]
    return s

#-----------------------
def everyOther(A, startAt):
    s = ""
    for i in range(startAt, len(A), 2):
        s += A[i]
    return s