webinar-for-loops-2021-04-10

# WEBINAR: for loops

# FOR LOOPS are used for repeating actions for every element
# in a container like a list, string, tuple, etc...
myList = ["Gilligan", "Scooby", "Agent Scully"] # tv characters
myTuple = ("Gilligan", "Castaway002", "red", "crew") # things about Gilligan

for item in myList:
    print(item)

for item in myTuple:
    print(item)

mySet = {"Gilligan", "Maynard", "Kelp"} # Bob Denver roles
for item in mySet:
    print(item)

myString = "Just sit right back and we'll talk about Gilligan and company."
# for char in myString: # commenting out so we don't print so much...
#     print(char)

# how about looping over dictionaries?
scoobies = {
    "Scooby": "a blue collar",
    "Shaggy": "green",
    "Velma": "orange",
    "Daphne": "purple",
    "Fred": "an ascot"
}
for key in scoobies:
    # someDict[key] --> value of that key
    # print(key, scoobies[key])
    print("{} wears {}.".format(key, scoobies[key]))

# another way to loop over dictionaries
for key, value in scoobies.items(): # 2 loop vars with dictionary items method
    print("{} always wears {}.".format(key, value))

for item in range(5): # range() makes an iterable sequence from an integer
    print(item)

# what if I'm interesting in the index position?
for i in range(len(myList)):
    print("{} is at position {}".format(myList[i], i))

for i, item in enumerate(myList): # enumerate() also gets you 2 loop vars: index and value at that index
    print(i,item)

# CA 6.10.1
# "Simon Says" is a memory game where "Simon" outputs a sequence of 10 characters
# (R, G, B, Y) and the user must repeat the sequence. Create a for loop that compares
# the two strings. For each match, add one point to user_score.
# Upon a mismatch, end the game. Ex: The following patterns yield a user_score of 4:

simon_pattern = 'RRGBRYYBGY'
user_pattern  = 'RRGBBRYBGY'
user_score = 0
for i in range(len(simon_pattern)):
    if simon_pattern[i] == user_pattern[i]:
        user_score += 1
    else:
        break
print("User score:", user_score)

# HTML is plain text... strings!
myContainer = ("peanut butter", "bread", "milk", "cheese puffs")
# we want this output:
# <ul>
# <li>peanut butter</li>
# <li>bread</li>
# <li>milk</li>
# <li>cheese puffs</li>
# </ul>
myHTMLString = "<ul>\n"
for item in myContainer:
    myHTMLString += "<li>{}</li>\n".format(item)
myHTMLString += "</ul>"
print(myHTMLString)

# use \ for escaping (excluding) characters, or special escaped char values like \n, \t, etc