#!/usr/bin/env python
# coding: utf-8

# If Statements
# ===
# 
# If statements are at the heart of almost all decision-making in programming. If statements allow you to treat some data differently than the rest of your data.

# In[1]:


# Example.
names = ['devin', 'killian', 'eric', 'matt', 'psalm', 'roger']

for name in names:
    print(f"Hello, {name}.")
    if name == 'matt':
        print("  Please, no puns today!")


# Conditional Statements
# ---
# 
# Conditional statements evaluate to True or False.

# In[1]:


True


# In[3]:


False


# In[4]:


5 == 5


# In[6]:


3 == 5


# In[12]:


age = 17

age == 18
age > 18
age < 18
age >= 18
age <= 18
age != 18 # age is not equal to 18?


# In[16]:


artists = ['prince', 'frieda kahlo', 'stan lee', 'isaac asimov']

'stan lee' in artists    


# In[ ]:


all_students = [...]

eligible_voters = []

for student in all_students:
    if student.age >= 18:
        eligible_voters.append(student)


# Simple if statements
# ---
# 
# You're only interested in one condition.

# In[17]:


ages = [16, 18, 11, 17, 16, 17, 19, 18, 21, 45, 89, 1, 7]

for age in ages:
    if age >= 18:
        print("Hey, did you know you can vote?!")


# If-else statements
# ---
# 
# You're interested in one condition, but you also want to do something else with everyone who doesn't meet that condition.

# In[18]:


ages = [16, 18, 11, 17, 16, 17, 19, 18, 21, 45, 89, 1, 7]

for age in ages:
    if age >= 18:
        print("Hey, did you know you can vote?!")
    else:
        print("Grow up! And some day you'll be able to vote.")


# If-elif-else statements
# ---
# 
# You're interested in several specific conditions.

# In[22]:


ages = [16, 18, 11, 17, 16, 17, 19, 18, 21, 45, 89, 1, 7]

for age in ages:
    if age >= 18:
        print("Hey, did you know you can vote?!")
    elif age <= 16:
        print("Grow up! And some day you'll be able to vote.")
    else:
        print("Please get ready to register to vote as soon as you turn 18!")


# If-if-if statements
# ---
# 
# You want to test a bunch of situations, and any or all conditions can be met.

# In[21]:


philip_pizza = ['sardines', 'onions']

# Pizza making code.
if 'pepperoni' in philip_pizza:
    print("Adding pepperoni.")
if 'sardines' in philip_pizza:
    print("Adding sardines.")
if 'mushrooms' in philip_pizza:
    print("Adding mushrooms.")
if 'onions' in philip_pizza:
    print("Adding onions.")