AWK, Bash, C, Lua, Node.js, Perl, Python and Ruby solutions for week 115, part 2

1 files changed, 71 insertions, 0 deletions

diff --git a/challenge-115/abigail/c/ch-2.c b/challenge-115/abigail/c/ch-2.c
new file mode 100644
index 0000000000..975aace0ef
--- /dev/null
+++ b/challenge-115/abigail/c/ch-2.c
@@ -0,0 +1,71 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+# include <ctype.h>
+
+/*
+ * See ../README.md
+ */
+
+/*
+ * Run as: cc -o ch-2.o ch-2.c; ./ch-2.o < input-file
+ */
+
+# define NR_OF_DIGITS 10
+# define ZERO         '0'
+
+int main (void) {
+    char *  line    = NULL;
+    size_t  len     = 0;
+    size_t  str_len;
+
+    while ((str_len = getline (&line, &len, stdin)) != -1) {
+        /*
+         * Read in a line of data. Count the number of digits,
+         * and put them in an array 'digits'.
+         */
+        char * line_ptr = line;
+        int digits [NR_OF_DIGITS];
+        for (size_t i = 0; i < NR_OF_DIGITS; i ++) {
+            digits [i] = 0;
+        }
+        while (* line_ptr) {
+            if (isdigit (* line_ptr)) {
+                digits [* line_ptr - ZERO] ++;
+            }
+            line_ptr ++;
+        }
+
+        /*
+         * Find the lowest even digit.
+         */
+        int last = -1;
+        for (ssize_t i = NR_OF_DIGITS - 2; i >= 0; i -= 2) {
+            if (digits [i]) {
+                last = i;
+            }
+        }
+
+        /*
+         * Skip if the input does not contain an even digit.
+         */
+        if (last < 0) {
+            continue;
+        }
+        digits [last] --;
+
+        /*
+         * Print the output
+         */
+        for (ssize_t i = NR_OF_DIGITS - 1; i >= 0; i --) {
+            for (int j = 0; j < digits [i]; j ++) {
+                printf ("%zu", i);
+            }
+        }
+        printf ("%d\n", last);
+
+    }
+    free (line);
+
+    return (0);
+}