ch2

19 files changed, 616 insertions, 0 deletions

diff --git a/ch1/char_hist.c b/ch1/char_hist.c
new file mode 100644
index 0000000..312df76
--- /dev/null
+++ b/ch1/char_hist.c
@@ -0,0 +1,30 @@
+#include<stdio.h>
+
+#define CHARSET_LENGTH 128;
+
+/*
+ * Prints a histogram of the lengths of words in its input.
+ */
+main() {
+    int c, i;
+    int count;
+    int length = CHARSET_LENGTH;
+    int c_counts[length];
+
+    for (i = 0; i < length; ++i) {
+        c_counts[i] = 0;
+    }
+
+    while ((c = getchar()) != EOF) {
+        ++c_counts[c];
+    }
+
+    for (i = 0; i < length; ++i) {
+        count = c_counts[i];
+
+        if (count > 0 && (i != ' ' && i != '\t' && i != '\n' )) {
+            printf("%c\t", i);
+            printf("%d\n", count);
+        }
+    }
+}
diff --git a/ch1/copier.c b/ch1/copier.c
new file mode 100644
index 0000000..eeade8e
--- /dev/null
+++ b/ch1/copier.c
@@ -0,0 +1,29 @@
+#include <stdio.h>
+
+/* Copy input to output; 1st version */
+//main() {
+//    int c; 
+//
+//    c = getchar();
+//    
+//    while (c != EOF) {
+//        putchar(c);
+//        c = getchar();
+//    }
+//}
+
+/* Copy input to output; 2nd version */
+main() {
+    int c;
+
+    while ((c = getchar()) != EOF) {
+        putchar(c);
+    }
+}
+
+//main() {
+//    printf("%d", EOF);
+//    getchar();
+//    printf("%d", getchar());
+//    printf("%d", getchar());
+//}
diff --git a/ch1/counter.c b/ch1/counter.c
new file mode 100644
index 0000000..a1b9927
--- /dev/null
+++ b/ch1/counter.c
@@ -0,0 +1,29 @@
+#include<stdio.h>
+
+/* 
+ * Count characters in input; 1st version 
+ */
+//main() {
+//    long nc;
+//
+//    nc = 0;
+//
+//    while (getchar() != EOF)
+//        ++nc;
+//
+//
+//    printf("%ld\n", nc);
+//}
+
+/*
+ * Count characters in input; 2nd version
+ */
+main() {
+    long nc;
+
+
+    for (nc = 0; getchar() != EOF; ++nc)
+        ;
+
+    printf("%ld\n", nc);
+}
diff --git a/ch1/ctof.c b/ch1/ctof.c
new file mode 100644
index 0000000..b95e20a
--- /dev/null
+++ b/ch1/ctof.c
@@ -0,0 +1,36 @@
+#include<stdio.h>
+
+#define LOWER 0;
+#define UPPER 300;
+#define STEP 20;
+
+float ctof(int c);
+
+/*
+ * Print Celcius-Fahrenheit table for celcius = 0, 20, ... 300.
+ */
+main() {
+    float fahr, celcius;
+    int lower, upper, step;
+
+    lower = LOWER;      // lower limit of temperature table
+    upper = UPPER;    // upper limit of temperature table
+    step = STEP;      // step size
+
+    celcius = lower;
+
+    printf("%3s %6s\n", "C", "F");
+
+    while (celcius <= upper) {
+        fahr = ctof(celcius);
+        printf("%3.0f %6.1f\n", celcius, fahr);
+        celcius = celcius + step;
+    }
+}
+
+/*
+ * Convert Celcius to Fahrenheit
+ */
+float ctof(int celcius) {
+    return (9.0 / 5.0) * celcius + 32.0;
+}
diff --git a/ch1/ftoc.c b/ch1/ftoc.c
new file mode 100644
index 0000000..70b994a
--- /dev/null
+++ b/ch1/ftoc.c
@@ -0,0 +1,37 @@
+#include<stdio.h>
+
+#define     LOWER   0       // lower limit of table 
+#define     UPPER   300     // upper limit of table 
+#define     STEP    20      // step size
+
+float ftoc(int fahr);
+
+/*
+ * Print Fahrenheit-Celcius table for fahr = 0, 20, ... 300.
+ */
+main() {
+    float fahr, celcius;
+    int lower, upper, step;
+
+    lower = LOWER;      // lower limit of temperature table
+    upper = UPPER;    // upper limit of temperature table
+    step = STEP;      // step size
+
+    fahr = lower;
+
+    printf("%3s %6s\n", "F", "C");
+
+    //    while (fahr <= upper) {
+    //        celcius = 5.0 / 9.0 * (fahr - 32.0);
+    //        printf("%3.0f %6.1f\n", fahr, celcius);
+    //        fahr = fahr + step;
+    //    }
+
+    for (fahr = UPPER; fahr >= LOWER; fahr = fahr - STEP) {
+        printf("%3.0f %6.1f\n", fahr, ftoc(fahr));
+    }
+}
+
+float ftoc(int fahr) {
+    return (5.0 / 9.0) * (fahr - 32);
+}
diff --git a/ch1/hello.c b/ch1/hello.c
new file mode 100644
index 0000000..b1ad928
--- /dev/null
+++ b/ch1/hello.c
@@ -0,0 +1,8 @@
+#include<stdio.h>
+
+main() {
+    printf("hello, ");
+    printf("world.");
+    printf("\n");
+}
+ 
diff --git a/ch1/line_counter.c b/ch1/line_counter.c
new file mode 100644
index 0000000..0447aa7
--- /dev/null
+++ b/ch1/line_counter.c
@@ -0,0 +1,16 @@
+#include<stdio.h>
+
+/*
+ * Count lines in input
+ */
+main() {
+    int c, nl;
+
+    nl = 0;
+
+    while ((c = getchar()) != EOF)
+        if (c == '\n')
+            ++nl;
+
+    printf("%d\n", nl);
+}
diff --git a/ch1/longest_line.c b/ch1/longest_line.c
new file mode 100644
index 0000000..58f2a72
--- /dev/null
+++ b/ch1/longest_line.c
@@ -0,0 +1,58 @@
+#include<stdio.h>
+#define MAXLENGTH 1000
+
+int get_line(char line[], int maxlength);
+void copy(char to[], char from[]);
+
+/*
+ * MAIN
+ * Prints longest line in STDIN.
+ */
+main() {
+    int len; // current line length
+    int max; // maximum length seen so far
+    char line[MAXLENGTH]; // current input line
+    char longest[MAXLENGTH]; // longest line saved here
+
+    max = 0;
+    while ((len = get_line(line, MAXLENGTH)) > 0)
+        if (len > max) {
+            max = len;
+            copy(longest, line);
+        }
+    if (max > 0) // there was a line
+        printf("%d\t", max);
+        printf("%s", longest);
+    return 0;
+}
+
+/*
+ * GET_LINE
+ * Read STDIN into LINE up to MAXLENGTH and return its length. 
+ * Returns the length of a the line.
+ */
+int get_line(char line[], int maxlength) {
+    int c, i;
+
+    for (i = 0; i < maxlength - 1 && (c = getchar()) != EOF && c != '\n'; ++i)
+        line[i] = c;
+    if (c == '\n') {
+        line[i] = c;
+        ++i;
+    }
+    line[i] = '\0';
+    return i;
+}
+
+/*
+ * COPY
+ * Copy FROM into TO; assume TO is big enough.
+ */
+void copy(char to[], char from[]) {
+    int i;
+
+    i = 0;
+    while ((to[i] = from[i]) != '\0')
+        ++i;
+}
+
diff --git a/ch1/no_trailers.c b/ch1/no_trailers.c
new file mode 100644
index 0000000..80dbc0f
--- /dev/null
+++ b/ch1/no_trailers.c
@@ -0,0 +1,72 @@
+#include<stdio.h>
+
+#define MAXLENGTH 1000
+
+int get_line(char line[], int maxlength);
+void strip_line(char line[], int length);
+void copy(char to[], char from[]);
+
+/*
+ * MAIN
+ * Removes all trailing whitespace and blank lines from STDIN.
+ */
+int main() {
+    int len; // current line length
+    char line[MAXLENGTH]; // current input line
+
+    while ((len = get_line(line, MAXLENGTH)) > 0) {
+        strip_line(line, len);
+        if (line[0] != '\0')
+            printf("%s\n", line);
+    }
+    return 0;
+}
+
+/*
+ * GET_LINE
+ * Read STDIN into LINE up to MAXLENGTH and return its length. 
+ * Returns the length of a the line.
+ */
+int get_line(char line[], int maxlength) {
+    int c, i;
+
+    for (i = 0; i < maxlength - 1 && (c = getchar()) != EOF && c != '\n'; ++i)
+        line[i] = c;
+    if (c == '\n') {
+        line[i] = c;
+        ++i;
+    }
+    line[i] = '\0';
+    return i;
+}
+
+/*
+ * STRIP_LINE
+ * Remove all whitespace from end of LINE of given LENGTH.
+ */
+void strip_line(char line[], int length) {
+    int i, c;
+
+    for (i = --length; i >= 0; --i) {
+        c = line[i];
+
+        if (c == ' ' || c == '\t' || c == '\n')
+            line[i] = '\0';
+        else 
+            break;
+    }
+}
+
+
+/*
+ * COPY
+ * Copy FROM into TO; assume TO is big enough.
+ */
+void copy(char to[], char from[]) {
+    int i;
+
+    i = 0;
+    while ((to[i] = from[i]) != '\0')
+        ++i;
+}
+
diff --git a/ch1/num_digits.c b/ch1/num_digits.c
new file mode 100644
index 0000000..c25fc29
--- /dev/null
+++ b/ch1/num_digits.c
@@ -0,0 +1,29 @@
+#include<stdio.h>
+
+/*
+ * Count digits, whitespace, and other characters.
+ */
+main() {
+    int c, i, nwhite, nother;
+    int ndigit[10];
+
+    nwhite = nother = 0;
+
+    for (i = 0; i < 10; ++i)
+        ndigit[i] = 0;
+
+    while ((c = getchar()) != EOF)
+        if (c >= '0' && c <= '9')
+            ++ndigit[c - '0'];
+        else if (c == ' ' || c == '\n' || c == '\t')
+            ++nwhite;
+        else 
+            ++nother;
+
+    printf("digits =");
+
+    for (i = 0; i < 10; ++i)
+        printf(" %d", ndigit[i]);
+    printf(", whitespace = %d, other = %d\n",
+            nwhite, nother);
+}
diff --git a/ch1/one_word.c b/ch1/one_word.c
new file mode 100644
index 0000000..8d50542
--- /dev/null
+++ b/ch1/one_word.c
@@ -0,0 +1,16 @@
+#include<stdio.h>
+
+/*
+ * Print input one word per line.
+ */
+main() {
+    int c;
+
+    while ((c = getchar()) != EOF) {
+        if (c == ' ' || c == '\n' || c == '\t')
+            putchar('\n');
+        else {
+            putchar(c);
+        }
+    }
+}
diff --git a/ch1/power.c b/ch1/power.c
new file mode 100644
index 0000000..8bca4fd
--- /dev/null
+++ b/ch1/power.c
@@ -0,0 +1,28 @@
+#include<stdio.h>
+
+int power(int m, int n);
+
+/*
+ * Test power function
+ */
+main() {
+    int i;
+
+    for (i = 0; i < 10; ++i)
+        printf("%d %d %d\n", i, power(2, i), power(-3, i));
+
+    return 0;
+}
+
+/*
+ * Raise base to n-th power; n >= 0
+ */
+int power(int base, int n) {
+    int i, p;
+
+    p = 1;
+
+    for (i = 1; i <= n; ++i)
+        p = p * base;
+    return p;
+}
diff --git a/ch1/reverse.c b/ch1/reverse.c
new file mode 100644
index 0000000..98edd98
--- /dev/null
+++ b/ch1/reverse.c
@@ -0,0 +1,70 @@
+#include<stdio.h>
+
+#define MAXLENGTH 1000
+
+// Prototypes
+int get_line(char line[], int maxlength);
+void line_copy(char to[], char from[]);
+void reverse_copy(char to[], char from[], int length);
+
+/*
+ * MAIN
+ * Reverse all lines on STDIN.
+ */
+int main() {
+    int len; // current line length
+    char line[MAXLENGTH]; // current input line
+    char reversed_line[MAXLENGTH]; // current reversed line
+
+    while ((len = get_line(line, MAXLENGTH)) > 0) {
+        reverse_copy(reversed_line, line, len);
+        printf("%s\n", reversed_line);
+    }
+    return 0;
+}
+
+/*
+ * GET_LINE
+ * Read STDIN into LINE up to MAXLENGTH.
+ * Returns the length of LINE.
+ */
+int get_line(char line[], int maxlength) {
+    int c, i;
+
+    for (i = 0; i < maxlength - 1 && (c = getchar()) != EOF && c != '\n'; ++i)
+        line[i] = c;
+    if (c == '\n') {
+        line[i] = c;
+        ++i;
+    }
+    line[i] = '\0';
+    return i;
+}
+
+/*
+ * LINE_COPY
+ * Copy FROM into TO; assume TO is big enough.
+ */
+void line_copy(char to[], char from[]) {
+    int i;
+
+    i = 0;
+    while ((to[i] = from[i]) != '\0')
+        ++i;
+}
+
+/*
+ * REVERSE_COPY
+ * Copy FROM into TO (of length LENGTH) in reverse order; assume TO is big
+ * enough.
+ */
+void reverse_copy(char to[], char from[], int length) {
+    int i;
+
+    for (i = 0; i < length; ++i) {
+        to[length - 1 - i] = from[i];
+    }
+
+    to[length] = '\0';
+}
+
diff --git a/ch1/too_long.c b/ch1/too_long.c
new file mode 100644
index 0000000..dcc6ed4
--- /dev/null
+++ b/ch1/too_long.c
@@ -0,0 +1,39 @@
+#include<stdio.h>
+
+#define MAXLENGTH 1000
+
+int get_line(char line[], int maxlength);
+void copy(char to[], char from[]);
+
+/*
+ * MAIN
+ * Print all lines larger than 80 characters.
+ */
+main() {
+    int len; // current line length
+    char line[MAXLENGTH]; // current input line
+
+    while ((len = get_line(line, MAXLENGTH)) > 0)
+        if (len > 80) {
+            printf("%s", line);
+        }
+    return 0;
+}
+
+/*
+ * GET_LINE
+ * Read STDIN into LINE up to MAXLENGTH and return its length. 
+ * Returns the length of a the line.
+ */
+int get_line(char line[], int maxlength) {
+    int c, i;
+
+    for (i = 0; i < maxlength - 1 && (c = getchar()) != EOF && c != '\n'; ++i)
+        line[i] = c;
+    if (c == '\n') {
+        line[i] = c;
+        ++i;
+    }
+    line[i] = '\0';
+    return i;
+}
diff --git a/ch1/wc.c b/ch1/wc.c
new file mode 100644
index 0000000..4a5007d
--- /dev/null
+++ b/ch1/wc.c
@@ -0,0 +1,29 @@
+#include<stdio.h>
+
+#define     IN      1   // inside a word
+#define     OUT     0   // outside a word
+
+/*
+ * Count lines, words, and characters in input.
+ */
+main() {
+    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);
+}
diff --git a/ch1/whitespace_converter.c b/ch1/whitespace_converter.c
new file mode 100644
index 0000000..6fee3bd
--- /dev/null
+++ b/ch1/whitespace_converter.c
@@ -0,0 +1,18 @@
+#include<stdio.h>
+
+/*
+ * Convert concurrent blanks to single blank.
+ */
+main() {
+    int c;
+
+    while ((c = getchar()) != EOF) {
+        if (c == ' ') {
+            while ((c = getchar()) == ' ') 
+                ;
+            putchar(' ');
+        }
+
+        putchar(c);
+    }
+}
diff --git a/ch1/whitespace_counter.c b/ch1/whitespace_counter.c
new file mode 100644
index 0000000..ea441e2
--- /dev/null
+++ b/ch1/whitespace_counter.c
@@ -0,0 +1,22 @@
+#include<stdio.h>
+
+/*
+ * Count whitespace in input
+ */
+main() {
+    int c, n_whitespace;
+
+    n_whitespace = 0;
+
+    while ((c = getchar()) != EOF) {
+        if (c == '\n')
+            ++n_whitespace;
+        if (c == '\t')
+            ++n_whitespace;
+        if (c == ' ')
+            ++n_whitespace;
+    }
+
+
+    printf("%d\n", n_whitespace);
+}
diff --git a/ch1/whitespace_translator.c b/ch1/whitespace_translator.c
new file mode 100644
index 0000000..efb52b2
--- /dev/null
+++ b/ch1/whitespace_translator.c
@@ -0,0 +1,26 @@
+#include<stdio.h>
+
+/*
+ * Translate invisible whitespace characters to visible
+ * representations.
+ */
+main() {
+    int c;
+
+    while ((c = getchar()) != EOF) {
+        if (c == 8) {
+            printf("\\b");
+            continue;
+        }
+        if (c == 9) {
+            printf("\\t");
+            continue;
+        }
+        if (c == '\\') {
+            printf("\\\\");
+            continue;
+        }
+
+        putchar(c);
+    }
+}
diff --git a/ch1/word_hist.c b/ch1/word_hist.c
new file mode 100644
index 0000000..965c1b9
--- /dev/null
+++ b/ch1/word_hist.c
@@ -0,0 +1,24 @@
+#include<stdio.h>
+
+/*
+ * Prints a histogram of the lengths of words in its input.
+ */
+main() {
+    int c;
+    int count;
+
+    while ((c = getchar()) != EOF) {
+        if (c == '\n' || c == '\t' || c == ' ') {
+
+            while (count > 0) {
+                printf("%s", "*");
+                --count;
+            }
+
+            if (count > 0) {
+                printf("\n");
+            }
+        } else
+            ++count;
+    }
+}