C solution for week 110, part 2

2 files changed, 84 insertions, 0 deletions

diff --git a/challenge-110/abigail/README.md b/challenge-110/abigail/README.md
index c8c826c8cd..33d02ed67b 100644
--- a/challenge-110/abigail/README.md
+++ b/challenge-110/abigail/README.md
@@ -78,6 +78,7 @@ sex,m,m,f,f
 ### Solutions
 * [AWK](awk/ch-2.awk)
 * [Bash](bash/ch-2.ch)
+* [C](c/ch-2.c)
 * [Perl](perl/ch-2.pl)
 
 ### Blog
diff --git a/challenge-110/abigail/c/ch-2.c b/challenge-110/abigail/c/ch-2.c
new file mode 100644
index 0000000000..fe91fbaec8
--- /dev/null
+++ b/challenge-110/abigail/c/ch-2.c
@@ -0,0 +1,83 @@
+# 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) {
+    char *  text = NULL;
+    size_t  len  = 0;
+    size_t  str_len;
+
+    if ((str_len = getdelim (&text, &len, '\0', stdin)) == -1) {
+        perror ("Failed to read stdin");
+        exit (1);
+    }
+    /*
+     * Count the number of input lines and columns.
+     */
+    size_t nr_of_lines   = 0;
+    size_t nr_of_columns = 0;
+    char * ptr = text;
+    while (* ptr) {
+        if (nr_of_lines == 0) {
+            if (* ptr == ',' || * ptr == '\n') {
+                nr_of_columns ++;
+            }
+        }
+        if (* ptr ++ == '\n') {
+            nr_of_lines ++;
+        }
+    }
+
+    /*
+     * Position pointer at the start of each input line;
+     * turn newlines into commas.
+     */
+    char ** outputs;
+    if ((outputs = (char **) malloc (nr_of_lines * sizeof (char *)))
+        == NULL) {
+        perror ("Malloc failed");
+        exit (1);
+    }
+    ptr = text;
+    size_t c = 0;
+    outputs [0] = ptr;
+    while (* ptr) {
+        if (* ptr == '\n') {
+            * ptr = ',';
+            if (* (ptr + 1) != '\0') {
+                outputs [++ c] = ptr + 1;
+            }
+        }
+        ptr ++;
+    }
+
+    /*
+     * For each line of output, print a column of input.
+     * Field are terminated by commas. For the output, proceed
+     * each field with a comma, except for the first output column.
+     */
+    for (size_t i = 0; i < nr_of_columns; i ++) {
+        for (size_t j = 0; j < nr_of_lines; j ++) {
+            if (j) {
+                printf (",");
+            }
+            while (* outputs [j] != ',') {
+                printf ("%c", * outputs [j] ++);
+            }
+            outputs [j] ++;
+        }
+        printf ("\n");
+    }
+
+
+    free (text);
+    return (0);
+}