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Answer to Exercise 1-14, page 24 Solution by Richard Heathfield Write a program to print a histogram of the frequencies of different characters in its input. Naturally, I've gone for a vertical orientation to match exercise 13. I had some difficulty ensuring that the printing of the X-axis didn't involve cheating. I wanted to display each character if possible, but that would have meant using is..

Answer to Exercise 1-13, page 24 Solution by Richard Heathfield 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. /* This program was the subject of a thread in comp.lang.c, because of the way it handled EOF. * The complaint was that, in the event of a text file's last ..

Answer to Exercise 1-12, page 21 Solution by Richard Heathfield Write a program that prints its input one word per line. #include int main(void) { int c; int inspace; inspace = 0; while((c = getchar()) != EOF) { if(c == ' ' || c == '\t' || c == '\n') { if(inspace == 0) { inspace = 1; putchar('\n'); } /* else, don't print anything */ } else { inspace = 0; putchar(c); } } return 0; }

Answer to Exercise 1-11, page 21 Solution by Dann Corbit How would you test the word count program? What kinds of input are most likely to uncover bugs if there are any? -------------------------------------------------------------------------------- It sounds like they are really trying to get the programmers to learn how to do a unit test. I would submit the following: 0. input file contains z..

Answer to Exercise 1-10, page 20 Category 0 Solution by Gregory Pietsch Category 1 Solution by Richard Heathfield 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 in an unambiguous way. Category 0 Gregory Pietsch pointed out that my solution was actually Category 1. He was quite ri..

Answer to Exercise 1-9, page 20 Solutions by Richard Heathfield , Chris Sidi , and Stig Brautaset Write a program to copy its input to its output, replacing each string of one or more blanks by a single blank. #include int main(void) { int c; int inspace; inspace = 0; while((c = getchar()) != EOF) { if(c == ' ') { if(inspace == 0) { inspace = 1; putchar(c); } } /* We haven't met 'else' yet, so w..

Answer to Exercise 1-8, page 20 Solution by Richard Heathfield Write a program to count blanks, tabs, and newlines. #include int main(void) { int blanks, tabs, newlines; int c; int done = 0; int lastchar = 0; blanks = 0; tabs = 0; newlines = 0; while(done == 0) { c = getchar(); if(c == ' ') ++blanks; if(c == '\t') ++tabs; if(c == '\n') ++newlines; if(c == EOF) { if(lastchar != '\n') { ++newlines..

Answer to Exercise 1-7, page 17 Solution by Richard Heathfield Write a program to print the value of EOF . #include int main(void) { printf("The value of EOF is %d\n\n", EOF); return 0; }

Answer to Exercise 1-6, page 17 Solution by Richard Heathfield Verify that the expression getchar() != EOF is 0 or 1. /* This program prompts for input, and then captures a character * from the keyboard. If EOF is signalled (typically through a * control-D or control-Z character, though not necessarily), * the program prints 0. Otherwise, it prints 1. * * If your input stream is buffered (and it..

Answer to Exercise 1-5, page 14 Solutions by Richard Heathfield and Chris Sidi Modify the temperature conversion program to print the table in reverse order, that is, from 300 degrees to 0. This version uses a while loop: #include int main(void) { float fahr, celsius; int lower, upper, step; lower = 0; upper = 300; step = 20; printf("C F\n\n"); celsius = upper; while(celsius >= lower) { fahr = (..