chapter 7: Dance Parties and Flower Parades with while Loops¶

7.1 A Simple while Loop¶

while 구문은 아래 구조로 되어 있다.

count = 1
while count <= 5:
    print(count)
    count += 1
print("Loop finished")

Mission #33: A Random Teleportation Tour¶

random 함수를 이용하여 임의로 움직이는 코드를 짜보자.

import time
import random
from mcpi.minecraft import Minecraft
mc = Minecraft.create()

count = 0
while count < 5:
    x = random.randrange(-127, 128)
    y = random.randrange(0, 64)
    z = random.randrange(-127, 128)

    mc.postToChat("x:"+str(x))
    mc.postToChat("Y:"+str(y))
    mc.postToChat("Z:"+str(z))
    mc.player.setTilePos(x, y, z)
    count += 1
    time.sleep(10)

7.2 Controlling Loops with a Count Variable¶

Mission #34: The Watery Curse¶

다음 미션을 수행해 보자.

from mcpi.minecraft import Minecraft
mc = Minecraft.create()

import time

count = 0

while count < 30:
    pos = mc.player.getPos()
    mc.setBlock(pos.x, pos.y, pos.z, 8)
    count += 1
    time.sleep(1)

Infinite while Loops¶

무한 반복을 의미 한다.

while True:
    print("Hello")


while True:
    print("Hello")
print("This line is never reached")

Mission #35: Flower Trail¶

skip this mission

7.3 Fancy Conditions¶

다음 코드를 보자 초기값은 while 루프가 실행되지만 사용자 입력값에 따라서 빠져나갈 수 있다.

continueAnswer = "Y"
coins = 0
while continueAnswer == "Y":
    coins = coins + 1
    continueAnswer = input("Continue? Y/N")
print("You have " + str(coins) + " coins")

Mission #36: Diving Contest¶

skip this mission

Boolean Operators and while Loops¶

boolean operator들도 while 문에 쓰인다.

password = "cats"
passwordInput = input("Please enter the password: ")
attempts = 0
while password != passwordInput and attempts < 3:
    attempts += 1
    passwordInput = input("Incorrect. Please enter the password: ")
if password == passwordInput:
    print("Password accepted.")

Checking a Range of Values in while Loops¶

while에 변수값 범위를 지정할 수 있다.

position = 0
while 0 <= position <= 10:
    position = int(input("Enter your position 0-10: "))
print(position)

Mission #37: Make a Dance Floor¶

다음 미션을 수행해 보자.

from mcpi.minecraft import Minecraft
mc = Minecraft.create()
import time

pos = mc.player.getTilePos()
floorX = pos.x - 2
floorY = pos.y - 1
floorZ = pos.z - 2
width = 5
length = 5
block = 41
mc.setBlocks(floorX, floorY, floorZ,
             floorX + width, floorY, floorZ + length, block)

while floorX <= pos.x <= floorX + width and floorZ <= pos.z <= floorZ + length:
    if block == 41:
        block = 57
    else:
        block = 41
    mc.setBlocks(floorX, floorY, floorZ,
                 floorX + width, floorY, floorZ + length, block)
    # get the player's position
    pos = mc.player.getTilePos()
    # wait 0.5 seconds
    time.sleep(0.5)

Nested if Statements and while Loops¶

whlile문 안에 if문이 들어가는 경우이다.

word = "mine"
count = 0
while count < 50:
    print(word)
    if word == "mine":
        word = "craft"
    else:
        word = "mine"

Mission #38: The Midas Touch¶

다음 미션을 수행해 보자. player가 지나간 자리는 모두 황금색으로 변하는 코드이다.

from mcpi.minecraft import Minecraft
mc = Minecraft.create()

air = 0
water = 9

while True:
    pos = mc.player.getTilePos()
    blockBelow = mc.getBlock(pos.x, pos.y - 1, pos.z)

    if blockBelow != air and blockBelow != water:
        # change the block below the player to gold
        mc.setBlock(pos.x, pos.y - 1, pos.z, 41)

7.4 Ending a while Loop with break¶

while문을 빠져 나갈때는 break를 쓴다.

while True:
    userInput = input("Enter a command: ")
    if userInput == "exit":
        break
    print(userInput)
 print("Loop exited")

Mission #39: Create a Persistent Chat with a Loop¶

다음 미션을 수행해 보자.

from mcpi.minecraft import Minecraft
mc = Minecraft.create()

userName = input("Enter your username: ")

while True:
    message = input("Enter your message: ")
    if message == "exit":
        break
    mc.postToChat(userName + ": " + message)

Mission #40: Hot and Cold¶

from mcpi.minecraft import Minecraft
import math
import time
import random
mc = Minecraft.create()

destX = random.randint(-127, 127)
destZ = random.randint(-127, 127)
destY = mc.getHeight(destX, destZ)

print(destX, destY, destZ)

block = 57
mc.setBlock(destX, destY, destZ, block)
mc.postToChat("Block set")

while True:
    pos = mc.player.getPos()
    distance = math.sqrt((pos.x - destX) ** 2 + (pos.z - destZ) ** 2)

    if distance == 0:
        break

    if distance > 100:
        mc.postToChat("Freezing")
    elif distance > 50:
        mc.postToChat("Cold")
    elif distance > 25:
        mc.postToChat("Warm")
    elif distance > 12:
        mc.postToChat("Boiling")
    elif distance > 6:
        mc.postToChat("On fire!")
    elif distance == 0:
        mc.postToChat("Found it")

7.4 What You Learned¶

while loops loops with conditions