Intro to Nested Looping Intro to Computer Science CS1510 Dr. Sarah Diesburg

Some Things From PA02 BMI  These were continuous regions. Set up your code to handle all areas…

Some Things From PA02 BMI  While this is valid mathematically, it is bad form in programming languages.  And it causes real problems when not set up properly.

Some Things From PA02 BMI  Recognize that these are four related categories. This makes it much easier to use if/elif/else.

Some Things From PA02 BMI  Recognize that these are four related categories. This makes it much easier to use if/elif/else.

Some Things From PA02 BMI  Recognize that these are four related categories. This makes it much easier to use if/elif/else.

Some Things From PA02 Triangle  Watch for messages that can only be printed under certain circumstances 4,3,5 is not in order “If the triangle is legal it also checks to see if the triangle is a right triangle.”

Nesting Nesting means to place one code structure inside of another Nested if statements If (a<1): if (a==0): print(“Hey, this is zero”) else: print(“This is a negative number”) 8

Nested Loops We can also nest loops Can be very powerful, but tricky! 9

The idea of nested looping for x in range(1,4): for y in range(1,5): print (x, '*', y, '=', (x*y)) How many times will this print??

Finding Out if a Number is Prime An integer, N, is prime if it is not evenly divisible by any of the numbers from 2 to N-1

Finding Out if a Number is Prime Is 41 a prime number? Is 77 a prime number?

Finding Out if a Number is Prime Is 413 a prime number? Is 419 a prime number?

Let’s Write a Design Paragraph Inputs? Steps to calculate result Outputs? 14

Finding Out if a Number is Prime Write a program that:  Asks for an integer greater than 2  Keeps prompting until it gets one  Checks the numbers from 2 to N-1 to see if N is evenly divisible by that number  Prints a message either way.

So how would we change this… To print information about all of the numbers from 2 to 100?  Nested Looping