Initial commit

7 files changed, 271 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..67f42e5
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+*
+
+!*.c
+!*.h
+!.gitignore
+!README.mdown
diff --git a/1-13_word-length-histogram.c b/1-13_word-length-histogram.c
new file mode 100644
index 0000000..1b4cdc0
--- /dev/null
+++ b/1-13_word-length-histogram.c
@@ -0,0 +1,73 @@
+#include <stdio.h>
+#define IN 1
+#define OUT 0
+#define MINWLENGTH 2
+#define MAXWLENGTH 20
+
+int main(void) {
+	/* Rundown of variables:
+	   c = current input char
+	   state = inside or outside a word
+	   ltrs = letter count
+	   wrds = word count
+	   lines = you should be shot if you don't know
+	   lengths = an array that keeps track of how often words up to x chars long
+	             occur.
+	*/
+
+	int c, state, ltrs, wrds, lines, wlen;
+	int lengths[MAXWLENGTH];
+	int i;
+	for (i = 0; i <= MAXWLENGTH; ++i) {
+		lengths[i] = 0;
+	}
+
+	ltrs = wrds = wlen = 0;
+	lines = 1;
+	state = OUT;
+	// Capture input until it ends
+	while ((c = getchar()) != EOF) {
+		// If it's whitespace, we've exited a word
+		if (c == '\n' || c == ' ' || c == '\t') {
+			if (state == IN) {
+				++wrds; // ...and should increase the count.
+				state = OUT;
+				/* Check to see if the word is eligible to be counted. */
+				if (wlen <= MAXWLENGTH) {
+					++lengths[wlen];
+				}
+				// Reset our word length now.
+				wlen = 0;
+			}
+			/* If it's a new line, we're still out of a word but need to increment the
+			   line count */
+			if (c == '\n') {
+				++lines;
+			}
+		} else {
+			/* If nothing else, we know it's just a random character or a letter. */
+			state = IN;
+			++wlen;
+		}
+		/* Everything that's input counts as a letter. */
+		++ltrs;
+	}
+	// This is ugly and I wish I knew a better way to do it.
+	printf("\nWORD LENGTH FREQUENCY\n\n         5   10   15   20   25   30   35   40   45   50   55   60   65   70   75\n");
+	int iter;
+	iter = MINWLENGTH;
+	while (iter <= MAXWLENGTH) {
+		i = lengths[iter];
+		if (i > 0) {
+			printf("%2d | ", iter);
+			while (i > 0) {
+				printf("#");
+				i = i-1;
+			}
+			printf("\n");
+		}
+		++iter;
+	}
+	printf("%d words, %d chars, %d lines.\n", wrds, ltrs, lines);
+	return 0;
+}
diff --git a/1-14_character-freq-histogram.c b/1-14_character-freq-histogram.c
new file mode 100644
index 0000000..14c4871
--- /dev/null
+++ b/1-14_character-freq-histogram.c
@@ -0,0 +1,51 @@
+#include <stdio.h>
+int main(void) {
+	/* Rundown of variables:
+	   c = current input char
+	   ltrs = letter count
+	   chars = string containing the characters the program will count
+	   lengths = the counts for each character
+	*/
+
+	int c;
+	int i = 0;
+	char chars[] = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
+	/* cnum is the number of characters found in the above string */
+	int cnum = 0;
+	while (chars[i] != '\0') {
+		cnum += 1;
+		++i;
+	}
+
+	/* This array need its members to be initialized to zero. */
+	int lengths[cnum];
+	for (i = 0; i <= cnum; ++i) {
+		lengths[i] = 0;
+	}
+
+	// Capture input until it ends
+	while ((c = getchar()) != EOF) {
+		for (i = 0; i < cnum; ++i) {
+			if (c == chars[i]) {
+				lengths[i] += 1;
+			}
+		}
+	}
+	// This is ugly and I wish I knew a better way to do it.
+	printf("\nCHARACTER FREQUENCY\n\n         5   10   15   20   25   30   35   40   45   50   55   60   65   70   75\n");
+	int iter = 0;
+	while (iter <= cnum) {
+		i = lengths[iter];
+		if (i > 0) {
+			printf("%2c | ", chars[iter]);
+			while (i > 0) {
+				printf("#");
+				i -= 1;
+			}
+			printf("\n");
+		}
+		++iter;
+	}
+	return 0;
+}
diff --git a/1-15_temp-convert-func.c b/1-15_temp-convert-func.c
new file mode 100644
index 0000000..aa59cf6
--- /dev/null
+++ b/1-15_temp-convert-func.c
@@ -0,0 +1,18 @@
+#include <stdio.h>
+
+#define MAX_F 300.0
+#define STEP 20.0
+
+float convert_to_c(float f) {
+	float celsius = (5.0 / 9.0) * (f - 32.0);
+	return celsius;
+}
+
+int main() {
+	printf("FAHRENHEIT   CELSIUS\n");
+	float i;
+	for (i = 0.0; i <= MAX_F; i += STEP) {
+		printf("%4.0f           %7.3f\n", i, convert_to_c(i));
+	}
+	return 0;
+}
diff --git a/1-16_longest-line.c b/1-16_longest-line.c
new file mode 100644
index 0000000..1f6e556
--- /dev/null
+++ b/1-16_longest-line.c
@@ -0,0 +1,52 @@
+#include <stdio.h>
+
+#define MAXLENGTH 100
+
+int get_line(char s[], int lim) {
+	/* Put as much as possible into a temp string, and count its length */
+	int c, i;
+
+	for (i = 0; i < lim && (c = getchar()) != EOF && c != '\n'; ++i) {
+		s[i] = c;
+	}
+	if (c == '\n') {
+		s[i] = c;
+		++i;
+	}
+	s[i] = '\0';
+	return i;
+}
+
+void copy(char from[], char to[]) {
+	int i = 0;
+
+	while ((to[i] = from[i]) != '\0') {
+		++i;
+	}
+}
+
+int main() {
+	int len, max;
+
+	char line[MAXLENGTH];
+	char longest[MAXLENGTH];
+
+	max = 0;
+	while ((len = get_line(line, MAXLENGTH)) > 0) {
+		if (len > max) {
+			max = len;
+			copy(line, longest);
+		}
+	}
+
+	printf("\nThe longest line is %3d characters long.\n", max);
+	printf("----------------------------------------\n");
+	if (max > 0) {
+		printf("%-s", longest);
+		if (max == MAXLENGTH && longest[max - 1] != '\n') {
+			printf("\n");
+		}
+	}
+
+	return 0;
+}
diff --git a/1-17_over-80.c b/1-17_over-80.c
new file mode 100644
index 0000000..dcf7058
--- /dev/null
+++ b/1-17_over-80.c
@@ -0,0 +1,62 @@
+#include <stdio.h>
+
+#define MINLENGTH 80
+
+/* Read as much as possible of a string and return its length. */
+int get_line(char s[]) {
+	int c, i;
+
+	for (i = 0; i < MINLENGTH - 1 && (c = getchar()) != EOF; ++i) {
+		s[i] = c;
+	}
+	if (c == '\n') {
+		s[i] = c;
+		++i;
+	}
+	s[i] = '\0';
+	return i;
+}
+
+int main() {
+	// longline is used as a boolean that tells us if it's a line worth printing
+	int longline = 0;
+
+	// len is simply a character counter, while c is the character itself.
+	int len, c;
+	char buffer[MINLENGTH];
+
+	while ((c = getchar()) != EOF) {
+		buffer[len] = c;
+
+		/* When we meet the end of the line, we need to print the rest of the line,
+		   but only if we're already in a long line. Otherwise, reset our state.
+		 */
+		if (c == '\n') {
+
+			if (longline == 1 && len < MINLENGTH - 1) {
+				buffer[len + 1] = '\0';
+				printf("%-s", buffer);
+			}
+
+			len = 0;
+			longline = 0;
+			continue;
+		}
+
+		/* When the buffer has filled up, output its contents! */
+		if (len == MINLENGTH) {
+			buffer[len + 1] = '\0';
+			printf("%-s", buffer);
+			len = 0;
+			longline = 1;
+			continue;
+		}
+
+		/* If neither of the above cases are caught, increment our counter and fetch
+		   more data.
+		 */
+		++len;
+	}
+
+	return 0;
+}
diff --git a/README.mdown b/README.mdown
new file mode 100644
index 0000000..7af39e0
--- /dev/null
+++ b/README.mdown
@@ -0,0 +1,9 @@
+As I was reading Kernighan and Ritchie's *The C Programming Language*, I felt 
+like I was learning the syntax and other superficial things, but not learning 
+the more practical lessons that I was sure I'd run into once I tried to make 
+something. So I chose to do the exercises. I didn't start until the middle of 
+Chapter 1, but better late than never!
+
+If you have suggestions or pointers, message me! I really want to learn C "the 
+right way". It's a fascinating, spartan, pretty language, and I want to become 
+good with it.