Exercise 1-10. Write a program to copy its input to its output, replacing each tab by t, each backspace by b, and each backslash by \. This makes tabs and backspaces visible. Approach The exercise is deceptively simple to state but teaches something subtle about C: the difference between a character’s value in the program …
Exercise 1-8. Write a program to count blanks, tabs, and newlines. Approach The solution maintains three independent counters and reads one character at a time using the canonical getchar() loop. The key design decision is using three separate if statements rather than else if. In this case a character can only ever be one thing …
Exercise 1-7. Write a program to print the value of EOF. This is one of those exercises that looks trivial — one printf and you’re done — but it opens the door to one of the most important design decisions in the C standard library. Before you can really understand why Chapter 1’s input loops …
Exercise 1-6. Verify that the expression getchar() != EOF is 0 or 1. What This Exercise Is Really About This is not a “write a loop” exercise — it is a verification exercise, and the thing being verified is a fundamental rule of C that surprises many beginners: every relational expression in C evaluates to …
Exercise 1-5. Modify the temperature conversion program to print the table in reverse order, that is, from 300 degrees to 0. Approach The original K&R temperature program counts up: it starts fahr at 0, adds the step each iteration, and stops when fahr > 300. Reversing the table means changing exactly three things: (1) start …
Exercise 1-3. Modify the temperature conversion program to print a heading above the table. What the Base Program Does K&R Section 1.2 introduces a program that prints a Fahrenheit-to-Celsius conversion table from 0 to 300 in steps of 20. It uses integer arithmetic — celsius = 5 * (fahr – 32) / 9 — and …