Exercise 1-15. Rewrite the temperature conversion program of Section 1.2 to use a function. Section 1.2 of K&R embeds the conversion formula directly inside main. It works — but it ties the formula to one spot in the code. This exercise asks you to extract that logic into a separate function called celsius. The payoff …
Exercise 1-13. Write a program to print a histogram of the lengths of words in its input. It is easy to draw the histogram with the bars horizontal; a vertical orientation is more challenging. Approach The program breaks into two clear phases: counting word lengths, then rendering the histogram. Counting reuses the IN/OUT state machine …
Exercise 1-12. Write a program that prints its input one word per line. Approach A word is any contiguous run of non-whitespace characters; spaces, tabs, and newlines are all separators. The challenge is not reading words — it is knowing when to emit the newline that separates them in the output. The solution borrows the …
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 1-7. 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 …