# From Flowcharts to Python Code An algorithm is like a recipe in a cook book. It is a step by step set of instructions that the computer will have to follow to solve a problem or complete a task. Algorithms consist of step by step instructions which are listed in order and will be executed in the same order, one instruction at a time: this is called sequencing. On occasions a set of instructions needs to be repeated several times which is done in programming using a loop: this is called iteration. Computers also have to take decisions as to whether or not to run a set of instructions or to bypass these instructions. In programming these decisions are coded using IF statements: this is called selection.

Complex algorithms can use a range of sequencing, iteration and selection blocks.

To design an algorithm you can draw a flowchart or write pseudo-code.

Your algorithm (flowchart or pseudo-code) can then be converted by a programmer using the programming language of their choice (e.g. Python, Java, Visual Basic, etc.)

#### Coding Challenges

We have designed five algorithms (See flowcharts below). Your task is to implement each of these algorithms using Python code.

Stopwatch AlgorithmLeap Year?Winter OlympicsTimes TableLogin Form
A stopwatch is used to record the duration of an event as a number of seconds. Our stopwatch algorithm will convert/format this number of seconds to calculate and display the matching number of hours, minutes and seconds, knowing that:

• 1 hour = 3600 seconds
• 1 minute = 60 seconds #### Python Code

Complete the code using the trinket below:

This algorithm is a good example of: Did you know that the next leap year will be in 2020? To find out if a year (e.g. 2020) is a leap year you can calculate the remainder of year (e.g. 2020) divided by 4. If this remainder is null, then the year is a leap year.

The following algorithm is used to test if a year is a leap year or not. #### Python Code

This algorithm is a good example of: The last Winter Olympics took place in 2018 in Pyeong Chang (South Korea). Winter Olympics take place every 4 years. So when would be the next winter Olympics?

The following algorithm can be used to display the dates of the next ten Winter Olympics. #### Python Code

This algorithm is a good example of: The following algorithm will be used to ask the end-user to enter a number. The program will then display the full times table, from 1 to 10, for this number. #### Python Code

This algorithm is a good example of: A login form should ask the user to enter their username and password. It will then check if these login details are correct before displaying either a welcome message or an error message. #### Python Code

This algorithm is a good example of: 