1 files changed, 66 insertions, 0 deletions
diff --git a/test/05-sort.c b/test/05-sort.c
new file mode 100644
index 0000000..829e0d1
--- /dev/null
+++ b/test/05-sort.c
@@ -0,0 +1,66 @@
+/* ARGS:  3 392 91 -2 -100 0 7 */
+/* EXPECT:
+-100, -2, 0, 3, 7, 91, 392, 
+36 cmps, 3 swaps
+392, 91, 7, 3, 0, -2, -100, 
+*/
+
+#include <stddef.h>
+
+int printf(const char *, ...);
+void *calloc(size_t, size_t);
+void qsort(void *, size_t nmemb, size_t size, int (const void *, const void *));
+int atoi(const char *);
+
+int
+icmp(const void *a, const void *b)
+{
+   int l = *(int *)a, r = *(int *)b;
+   return (l > r) - (l < r);
+}
+
+int nswp = 0, ncmp = 0;
+void
+revsort(int *xs, long lo, long hi)
+{
+   while (lo < hi) {
+      long i = lo - 1, p = hi + 1;
+      int pivot = xs[lo], tmp;
+      for (;;) {
+         do ++i; while (++ncmp, xs[i] > pivot);
+         do --p; while (++ncmp, xs[p] < pivot);
+         if (i >= p) break;
+         tmp = xs[i];
+         xs[i] = xs[p];
+         xs[p] = tmp;
+         ++nswp;
+      }
+      if (p + 1 >= hi) {
+         hi = p;
+      } else {
+         if (lo < p)
+            revsort(xs, lo, p);
+         lo = p + 1;
+      }
+   }
+}
+
+int
+main(int argc, char **argv)
+{
+   int N = argc - 1;
+   int *xs = calloc(N, sizeof *xs);
+
+   for (int i = 0; i < N; ++i)
+      xs[i] = atoi(argv[i+1]);
+   qsort(xs, N, sizeof *xs, icmp);
+   for (int i = 0; i < N; ++i)
+      printf("%d, ", xs[i]);
+   printf("\n");
+   revsort(xs, 0,N-1);
+   printf("%d cmps, %d swaps\n", ncmp, nswp);
+   for (int i = 0; i < N; ++i)
+      printf("%d, ", xs[i]);
+   printf("\n");
+   return N;
+}