diff options
| -rw-r--r-- | 1-01_hello-world.c | 14 | ||||
| -rw-r--r-- | 1-02_escape-sequences.c | 15 | ||||
| -rw-r--r-- | 1-03_temp-table-header.c | 29 | ||||
| -rw-r--r-- | 1-04_celsius_converter.c | 27 | ||||
| -rw-r--r-- | 1-05_backwards-table.c | 29 | ||||
| -rw-r--r-- | 1-06_eof-test.c | 15 | ||||
| -rw-r--r-- | 1-07_eof-value.c | 13 | ||||
| -rw-r--r-- | 1-08_space-counter.c | 29 | ||||
| -rw-r--r-- | 1-09_single-spacing.c | 27 | ||||
| -rw-r--r-- | 1-10_literal-escapes.c | 33 | ||||
| -rw-r--r-- | 1-11_word-count.c | 37 | ||||
| -rw-r--r-- | 1-12_one-word-per-line.c | 39 |
12 files changed, 307 insertions, 0 deletions
diff --git a/1-01_hello-world.c b/1-01_hello-world.c new file mode 100644 index 0000000..e02c87a --- /dev/null +++ b/1-01_hello-world.c @@ -0,0 +1,14 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-1: Run the "hello, world" program on your system. Experiment with + * leaving out parts of the program, to see what error messages you get. + * + * This is the typical first exercise. No need for me to putz with it. + */ + +int main(void) { + printf("Hello world!\n"); + return 0; +} diff --git a/1-02_escape-sequences.c b/1-02_escape-sequences.c new file mode 100644 index 0000000..8d122e0 --- /dev/null +++ b/1-02_escape-sequences.c @@ -0,0 +1,15 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-2: Experiment to find out what happens when printf()'s argument + * string contains \c, where 'c' is some character that's not \, t, b, n, or ". + * + * Answer: This file will not (normally) compile because \d is not a valid + * escape sequence. Your compiler may ignore this, however. + */ + +int main(void) { + printf("Hello world! \d\n"); + return 0; +} diff --git a/1-03_temp-table-header.c b/1-03_temp-table-header.c new file mode 100644 index 0000000..d0d069c --- /dev/null +++ b/1-03_temp-table-header.c @@ -0,0 +1,29 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-3: Modify the temperature conversion program to print a heading + * above the table. + * + * Answer: Just add a printf() or two before the table. + */ + +int main(void) { + float fahr, celsius; + int lower, upper, step; + + lower = 0; + upper = 300; + step = 20; + + fahr = lower; + + printf(" F | C\n"); + printf("------------\n"); + while (fahr <= upper) { + celsius = (5.0 / 9.0) * (fahr - 32.0); + printf(" %3.0f %6.1f\n", fahr, celsius); + fahr += step; + } + return 0; +} diff --git a/1-04_celsius_converter.c b/1-04_celsius_converter.c new file mode 100644 index 0000000..a397d9a --- /dev/null +++ b/1-04_celsius_converter.c @@ -0,0 +1,27 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-4: Write a program to print the corresponding Celsius to + * Fahrenheit table. + */ + +int main(void) { + float fahr, celsius; + int lower, upper, step; + + lower = 0; + upper = 300; + step = 20; + + celsius = lower; + + printf(" C | F\n"); + printf("------------\n"); + while (celsius <= upper) { + fahr = (celsius * (9.0 / 5.0)) + 32.0; + printf(" %3.0f %6.1f\n", celsius, fahr); + celsius += step; + } + return 0; +} diff --git a/1-05_backwards-table.c b/1-05_backwards-table.c new file mode 100644 index 0000000..a09619a --- /dev/null +++ b/1-05_backwards-table.c @@ -0,0 +1,29 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-5: Modify the temperature conversion program to print the table in + * reverse order, that is, from 300 degrees to 0. + * + * Answer: Ensure that fahr starts at upper and the while loop runs until zero. + */ + +int main(void) { + float fahr, celsius; + int lower, upper, step; + + lower = 0; + upper = 300; + step = 20; + + fahr = upper; + + printf(" F | C\n"); + printf("------------\n"); + while (fahr >= 0) { + celsius = (5.0 / 9.0) * (fahr - 32.0); + printf(" %3.0f %6.1f\n", fahr, celsius); + fahr -= step; + } + return 0; +} diff --git a/1-06_eof-test.c b/1-06_eof-test.c new file mode 100644 index 0000000..5214338 --- /dev/null +++ b/1-06_eof-test.c @@ -0,0 +1,15 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-6: Verify that the expression 'getchar() != EOF' is 0 or 1. + * + * Answer: Easy. + */ + +int main(void) { + int c; + c = (getchar() != EOF); + printf("%d\n", c); + return 0; +} diff --git a/1-07_eof-value.c b/1-07_eof-value.c new file mode 100644 index 0000000..aaf838b --- /dev/null +++ b/1-07_eof-value.c @@ -0,0 +1,13 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-7: Write a program to print the value of EOF. + * + * Answer: Just cast it to an integer placeholder in printf(). + */ + +int main(void) { + printf("%d\n", EOF); + return 0; +} diff --git a/1-08_space-counter.c b/1-08_space-counter.c new file mode 100644 index 0000000..0e00176 --- /dev/null +++ b/1-08_space-counter.c @@ -0,0 +1,29 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-8: Write a program to count blanks, tabs, and newlines. + * + * Answer: Run a loop with getchar() and check its value. Then add to the + * counts and spit them out at the end of the loop. + */ + +int main(void) { + char c; + int blanks, tabs, nls = 0; + + while ((c = getchar()) != EOF) { + if (c == ' ') { + blanks++; + } + if (c == '\t') { + tabs++; + } + if (c == '\n') { + nls++; + } + } + + printf("%d blanks, %d tabs, and %d newlines.\n", blanks, tabs, nls); + return 0; +} diff --git a/1-09_single-spacing.c b/1-09_single-spacing.c new file mode 100644 index 0000000..82447ee --- /dev/null +++ b/1-09_single-spacing.c @@ -0,0 +1,27 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-9: Write a program to copy its input to its output, replacing each + * string of one or more blanks by a single blank. + * + * Answer: Run a loop with getchar() and check its value. If it's a space, count + * it, but prevent further spaces from being printed. Anything else should + * simply be spat out. + */ + +int main(void) { + char c; + int spaces = 0; + + while ((c = getchar()) != EOF) { + if (c == ' ' && spaces == 0) { + putchar(c); + spaces++; + } else { + putchar(c); + } + } + + return 0; +} diff --git a/1-10_literal-escapes.c b/1-10_literal-escapes.c new file mode 100644 index 0000000..903fff4 --- /dev/null +++ b/1-10_literal-escapes.c @@ -0,0 +1,33 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * 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 in an unambiguous way. + * + * Answer: Run a loop with getchar() and check its value. When you run into a + * tab, backspace, or backslash, just output the two characters and move on. + */ + +int main(void) { + char c; + + while ((c = getchar()) != EOF) { + if (c == '\t') { + printf("\\t"); + continue; + } + if (c == '\b') { + printf("\\b"); + continue; + } + if (c == '\\') { + printf("\\\\"); + continue; + } + putchar(c); + } + + return 0; +} diff --git a/1-11_word-count.c b/1-11_word-count.c new file mode 100644 index 0000000..1b4056c --- /dev/null +++ b/1-11_word-count.c @@ -0,0 +1,37 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-11: How would you test the word count program? What kinds of + * input are most likely to uncover bugs if there are any? + * + * Answer: New lines (such as those caused by wrapping text) are most likely to + * introduce erroneous word counts, as well as symbols that are strung together + * but don't create actual words. + */ + +#define IN 1 +#define OUT 0 + +int main(void) { + int c, nl, nw, nc, state; + state = OUT; + nl = nw = nc = 0; + + while ((c = getchar()) != EOF) { + nc++; + if (c == '\n') { + nl++; + } + if (c == ' ' || c == '\n' || c == '\t') { + state = OUT; + } else if (state == OUT) { + state = IN; + nw++; + } + } + + printf("%d %d %d\n", nl, nw, nc); + + return 0; +} diff --git a/1-12_one-word-per-line.c b/1-12_one-word-per-line.c new file mode 100644 index 0000000..3f31d1d --- /dev/null +++ b/1-12_one-word-per-line.c @@ -0,0 +1,39 @@ +#include <stdio.h> + +/* The C Programming Language, 2nd Edition + * + * Exercise 1-12: Write a program that prints its input one word per line. + * + * Answer: Be sure to output letters when you're in a word, and a newline when + * you're out of one. + */ + +#define IN 1 +#define OUT 0 + +int main(void) { + int c, nl, nw, nc, state; + state = OUT; + nl = nw = nc = 0; + + while ((c = getchar()) != EOF) { + nc++; + if (c == '\n') { + nl++; + } + if (c == ' ' || c == '\n' || c == '\t') { + state = OUT; + putchar('\n'); + } else if (state == OUT) { + state = IN; + nw++; + } + if (state == IN) { + putchar(c); + } + } + + printf("%d %d %d\n", nl, nw, nc); + + return 0; +} |