Lesson 6: C++ toolchain and basics: Real-world case study

Concept Explanation

A real-world case study should feel closer to something you might actually build. Here, the focus is on a small timing example that measures how long a simple task takes. You will not optimize anything advanced yet. Instead, you will practice reading a realistic pattern, understanding where timing starts and ends, and presenting the result clearly. This is a good beginner example because it introduces useful standard-library tools while still keeping the program short and manageable.

Where to Put the Code

1. Start with variables and inputs. Keep includes, main function, and data types explicit.
2. Add processing logic in the middle section.
3. Finish with output and quick validation.

Command Reference

• Run the program and note both the computed result and the elapsed time.
• Change the loop size and compare how the timing output responds.
• Keep the timing logic easy to spot by separating setup, work, and reporting.
• Describe one practical place where measuring a task duration would be useful.

Step-by-step Guide

1. Compile and run the example to see the baseline result and timing output.
2. Identify which part of the code is the measured workload.
3. Modify the loop limit and compare the new timing with the original run.
4. Check that the printed sum still makes sense after your change.
5. Write a short note explaining why start and end points must wrap only the work you care about.

Practice Exercises

• Replace the summing loop with a loop that counts even numbers and measure that instead.
• Print the elapsed time in milliseconds rather than microseconds.
• Create a second workload and compare its runtime with the first one.

Coding Challenges

• Design a small benchmark that compares two simple approaches to the same task.
• Keep the timing example readable while making the measured work slightly more realistic.

Mini Practice Tasks

• Rename one variable so the timing section is clearer.
• Change the loop size and rerun the measurement.
• Write a one-line summary of what this program measures.