Lab 4: What is a List?

Lab 4: What is a List? Feb. 17–Feb. 21

Announcements • Make sure you are subscribed to announcements on Moodle. • Activity 4 will be due 48hrs after your lab ends

Key Concepts… • Variables • Script variable • Lists • Loops • Custom Blocks • We can create 3 types of blocks; command, reporter and predicate.

Activity 4: Hangman • Hangman Rules: • There is a secret word to be guessed • The player guesses letters in the word until either all letters are guessed and the word is known, or the player runs out of guesses. • The program should give the player feedback on every guess • The program should give the player feedback when they win or lose, say the number of guesses and the secret word.

Suggested Steps • Step 1: Choose a word • Step 2: Word  List. • Step 3: Report number of letters in Word • Step 4: Begin Guessing! • Step 5: Report number of guesses • Step 6: Display letters • Step 7: Report win or loss, play again?

Step 1: Choose a word • The Setter first enters the secret word by entering a response to an “ask” block. • The first thing we’ll need to do is have the game ask one player for a word. • We can do this using sensing blocks. • We can define answer by setting it to a variable

Step 1: Choose a word • Notice we created a block for “ask for word” • What does the shape tell us about the block • Command, reporter, or predicate?

Step 2: Word  List • The word is immediately hidden from view after the Setter finishes entering it. • After we have the word, we’ll need to store it letter by letter. • Create a script that will go through the word and store the letters, one by one, in a list. • Consider the blocks below.

Step 2: Word  List • Create variable letter_list • Again, notice the shape of this block.

Step 3: Report # of letters • The program starts by telling the Guesser how many letters are in the secret word. • We should tell the other player how long of a word they are guessing • Use the “say” block, “join” block, “length of list” block and the variables we just created.

Step 3: Report # of letters • “Length of list” block is a reporter block

Step 4: Begin Guessing • Guesser guesses a letter; the program tells the player whether their guess was right or wrong • Now, we want the second player to guess letters until they run out of guesses or they guess the entire word. • What kind of control blocks should we use; • To do something over and over? • To stop when something happens?

Step 4: Begin Guessing • List that shows correct letters as the game is being played. (similar to hangman blanks) • List that shows the guesses made by player

Step 4: Begin Guessing • Repeat until one of two things happen • Lives left equals zero or • Guess word, correctguess_list is equals to letter_list • If we want to repeat until this is TRUE…we will create _______ statements (reporter, predicate, command?)

Step 4: Begin Guessing • What belongs inside this repeat? • Simplify by creating code inside into a block

Step 4: Begin Guessing • Similar to “break word into list” • Use script variables • “Ask” player to make a guess

Step 4: Begin Guessing • When the guesser guesses a letter, we want to show them where it appears in to actual word, if it does. • Already created a list of blanks the same size as the actual word (correctguess_list) • Replace the blanks with the right letters as they are guessed. • What are the current list we have?

Step 4: Begin Guessing • What if the guess is wrong?

Step 5: Begin Guessing • If guess is wrong… • Report incorrect guess • Take away a life • Reports # of lives

Step 6: Display letters • The program displays the letters guessed correctly so far, in their proper location in the word. • Need to make sure the correctguess_list has the correct amount of blanks. • Use “add _ to list” • Allow the list to be seen on the stage.

Step 6: Display Letters • We want blanks to appear, and equal the same length of the word

Step 7: Report & Play again? • When the guesser either runs out of guesses or has successfully guessed the word the game ends. • Report a win or loss. • Ask if the player would like to play again • If yes, the game now ask the Guesser to become the Setter. • Repeat game. • If player wants to play again, what variables must be reset?

Step 7: Report & Play again • Now, Customize your game!!

Lab 4: What is a List?