C solutions for week 112

3 files changed, 105 insertions, 0 deletions

diff --git a/challenge-112/abigail/README.md b/challenge-112/abigail/README.md
index 574d51411f..c619dd35d2 100644
--- a/challenge-112/abigail/README.md
+++ b/challenge-112/abigail/README.md
@@ -35,6 +35,7 @@ Output: "/a"
 ### Solutions
 * [AWK](awk/ch-1.awk)
 * [Bash](bash/ch-1.sh)
+* [C](c/ch-1.c)
 * [Perl](perl/ch-1.pl)
 
 ### Blog
@@ -53,6 +54,7 @@ This is just finding the `$n + 1` Fibonacci number.
 ### Solutions
 * [AWK](awk/ch-2.awk)
 * [Bash](bash/ch-2.sh)
+* [C](c/ch-2.c)
 * [Perl](perl/ch-2.pl)
 
 ### Blog
diff --git a/challenge-112/abigail/c/ch-1.c b/challenge-112/abigail/c/ch-1.c
new file mode 100644
index 0000000000..d7445188a6
--- /dev/null
+++ b/challenge-112/abigail/c/ch-1.c
@@ -0,0 +1,78 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+# include <stdbool.h>
+
+/*
+ * See ../README.md
+ */
+
+/*
+ * Run as: cc -o ch-1.o ch-1.c; ./ch-1.o < input-file
+ */
+
+/*
+ * Here, we will "eliminate" parts (".", or ".." and its parent)
+ * by replacing the parts with slashes. Then we print the string,
+ * without printing 2 slashes in succession.
+ */
+
+int main (void) {
+    char *  line    = NULL;
+    size_t  len     = 0;
+    size_t  str_len;
+
+    while ((str_len = getline (&line, &len, stdin)) != -1) {
+        line [str_len - 1] = '/';
+        for (size_t i = 0; i < str_len; i ++) {
+            if (line [i] == '.' && line [i - 1] == '/') {
+                /* Component starts with a . */
+                if (line [i + 1] == '/') {
+                    line [i] = '/';  /* Current directory */
+                    continue;
+                }
+                else {
+                    if (line [i + 1] == '.' && line [i + 2] == '/') {
+                        /* Parent directory. */
+                        /* First wipe this component */
+                        line [i]     = '/';
+                        line [i + 1] = '/';
+                        /* Then wipe the previous component, if any. */
+                        /* First, skip the slashes */
+                        size_t j = i - 1;
+                        while (j && line [j] == '/') {
+                            j --;
+                        }
+                        /* Now, erase exactly one component */
+                        while (j && line [j] != '/') {
+                            line [j] = '/';
+                            j --;
+                        }
+                    }
+                }
+            }
+        }
+        /* Get rid of trailing slashes */
+        while (str_len > 1 && line [str_len - 1] == '/') {
+            str_len --;
+        }
+        /* Print string, eliminating double slashes */
+        bool slash = false;
+        for (size_t i = 0; i < str_len; i ++) {
+            if (line [i] == '/') {
+                if (slash) {
+                    continue;
+                }
+                slash = true;
+            }
+            else {
+                slash = false;
+            }
+            printf ("%c", line [i]);
+        }
+        printf ("\n");
+    }
+    free (line);
+
+    return (0);
+}
diff --git a/challenge-112/abigail/c/ch-2.c b/challenge-112/abigail/c/ch-2.c
new file mode 100644
index 0000000000..97c36677ab
--- /dev/null
+++ b/challenge-112/abigail/c/ch-2.c
@@ -0,0 +1,25 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+
+/*
+ * See ../README.md
+ */
+
+/*
+ * Run as: cc -o ch-2.o ch-2.c; ./ch-2.o < input-file
+ */
+
+int main (void) {
+    int n, f1, f2;
+
+    while (scanf ("%d", &n) == 1) {
+        for (f1 = 0, f2 = 1;n --;) {
+            f2 += f1;
+            f1  = f2 - f1;
+        }
+        printf ("%d\n", f2);
+    }
+
+    return (0);
+}