Intro., Input & Output (I/O), if, while, do-while, for

As an introduction to programming in C++, let's use an example program to convert between Fahrenheit and Celsius temperatures. These examples assume you already have some knowledge of a programming language involving variables and assignment, decision and looping statements, and input/output (I/O).

1. Minimal essentials, Output, semi-colon, comments (/* */), newline
2. Variables, I/O, expressions, comments (//), arithmetic, precedence
3. if statement, assignment (=), indentation, blocks {}, exit(-1), sanity checks (assert, system)
4. while loop, display format size (e.g. %4d, do loop
5. for loop

Note that in the examples above you can move the bar between the two windows to make one of them (top or bottom) larger.