Data Structures and Algorithms Week 1 C++ Basics Topics: 0 Introduction

Remembering the advice of divide and conquer, we can expand on this, and divide a problem into subproblems, and then write a function which solves each subproblem. Take the problem of

“Take 2 numbers from the user, order them so the lowest number is first, and then returning them to the user.”

This can be broken into subtasks;

1) Get input from user.
2) Find out which number is lower and if necessary;
3) Swap the 2 numbers.
4) Return the output to the user.

Each of these subtasks can be solved by a function – the main part of the program (or main function) is then responsible for declaring variables and calling functions when necessary. This means that each subproblem can be solved individually. It also tidies the code up and makes it easier to read, and if there is a problem with the program makes it easier to isolate where the problem is, by testing each function independently.