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Answer to Exercise 1-19, page 31 Solution by Richard Heathfield Write a function reverse(s) that reverses the character string s . Use it to write a program that reverses its input a line at a time. #include #define MAX_LINE 1024 void discardnewline(char s[]) { int i; for(i = 0; s[i] != '\0'; i++) { if(s[i] == '\n') s[i] = '\0'; } } int reverse(char s[]) { char ch; int i, j; for(j = 0; s[j] != '..

Answer to Exercise 1-18, page 31 Solution by Ben Pfaff and a modification thereof by Chris Sidi Write a program to remove all trailing blanks and tabs from each line of input, and to delete entirely blank lines. /* K&R2 1-18 p31: Write a program to remove trailing blanks and tabs from each line of input, and to delete entirely blank lines. The program specification is ambiguous: does "entirely b..

Answer to Exercise 1-17, page 31 Solution by "MJSR" Write a program to print all input lines that are longer than 80 characters. #include #define MINLENGTH 81 int readbuff(char *buffer) { size_t i=0; int c; while (i < MINLENGTH) { c = getchar(); if (c == EOF) return -1; if (c == '\n') return 0; buffer[i++] = c; } return 1; } int copyline(char *buffer) { size_t i; int c; int status = 1; for(i=0; i

Answer to Exercise 1-16, page 30 Solutions by Richard Heathfield and "386sx" Revise the main routine of the longest-line program so it will correctly print the length of arbitrarily long input lines, and as much as possible of the text. /* This is the first program exercise where the spec isn't entirely * clear. The spec says, 'Revise the main routine', but the true * length of an input line can..

Answer to Exercise 1-15, page 27 Solution by Richard Heathfield Rewrite the temperature conversion program of Section 1.2 to use a function for conversion. #include float FtoC(float f) { float c; c = (5.0 / 9.0) * (f - 32.0); return c; } int main(void) { float fahr, celsius; int lower, upper, step; lower = 0; upper = 300; step = 20; printf("F C\n\n"); fahr = lower; while(fahr

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..