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06/06

Objectives

  • Use git to sync your repository between your computer and github
  • Control the flow of logic through your program with if/else statements

GitX

http://gitx.frim.nl

![Image of Yaktocat] (http://3.bp.blogspot.com/-EIvLehT4a-U/Ti2OaDh9V-I/AAAAAAAAAeg/uCEpZpYg22o/s1600/Bildschirmfoto+2011-07-25+um+17.39.21.png)

Exercise #1

Push Thursdays homework to a remote repository. Once pushed, navigate to one of your peers github profiles. Fork their repository, make an edit, and submit a pull request.

If/Else

We've spent a little time talking about basic boolean expressions, such as:

BOOL isRaining = NO;
BOOL tenIsGreaterThanSeven = 10 > 7;

Now we can take it step further by introducing boolean logic. A basic pattern would be:

If expression is true, do something. Otherwise, do something else.

if (tenIsGreaterThanSeven) {
  NSLog(@"The world is at peace");
} else {
  NSLog(@"instanity");
}

It can also get very complex, sometimes resulting in multiple layers of nested statements. Boolean statements are the result of something that we haven't discussed yet: state. State is unavoidable, but introduces complexity into your program. The more state, the more room for error. If you find yourself with deeply nested boolean statements, odds are you need to take a step back and rethink that section of your program.

if (tenIsGreaterThanSeven) {
  if (!isRaining) {
    NSLog(@"everything is perfect");
  } else {
    NSLog(@"oops... forgot my umbrella. At least 10 > 7");
  }
} else {
  NSLog(@"insanity");
}

https://gist.github.com/mikekavouras/0b51b2481dd971d5113e

Exercise #2

There is an Xcode project on Github (https://github.com/accesscode-2-2/IfElse). Fork the repo and add some logic. When you're finished, create a pull request.

06/07

More boolean logic

We talked about boolean logic in the context of entering a club (https://gist.github.com/mikekavouras/a22d2512ed5014465622). Let's take it a step further. The following gist lays out requirements for different scenarios. Your job is to write the logic to implement these requirements. https://gist.github.com/mikekavouras/321df03634d9ebeca5ff

Exercises

Madlibs

This program should prompt the user for a minimum of six inputs (text inputs with at least one number) and then print out your "mad lib" result! Here is a sample partial run:

Sample input:

Enter an adjective: purple
Enter another adjective: ancient
Enter a noun: dragon
Enter another noun: spoon

Sample output:

Here is your mad lib!!
The purple bear went into the ancient house.
There she saw a dragon and a spoon.

Homework

https://github.com/accesscode-2-2/unit-0/blob/master/lessons/week-0/2015-02-06_homework.md