Sort benchmarks

1 files changed, 38 insertions, 0 deletions

diff --git a/sort-benchmark/pairs/sort.c b/sort-benchmark/pairs/sort.c
new file mode 100644
index 0000000..826a684
--- /dev/null
+++ b/sort-benchmark/pairs/sort.c
@@ -0,0 +1,38 @@
+#define _POSIX_C_SOURCE 200809L /* Required to use clock_gettime */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+typedef struct { int a, b; } pair_t;
+pair_t a[ARRAYSIZE];
+
+int compar(const void *x, const void *y) {
+        pair_t *p = (pair_t *)x;
+        pair_t *q = (pair_t *)y;
+        int d = p->a - q->a;
+        return d > 0 ? 1 : (d < 0 ? -1 : (q->b - p->b));
+}
+
+int main() {
+        srand(time(NULL));
+        for (int i = 0; i < ARRAYSIZE; i++) {
+                a[i].a = rand() % 1000000;
+                a[i].b = rand() % 1000000;
+        }
+
+        struct timespec begin;
+        clock_gettime(CLOCK_MONOTONIC, &begin);
+
+        qsort(a, ARRAYSIZE, sizeof(pair_t), compar);
+
+        struct timespec end;
+        clock_gettime(CLOCK_MONOTONIC, &end);
+        double time = end.tv_sec - begin.tv_sec +
+                (end.tv_nsec - begin.tv_nsec) / 1000000000.0;
+
+        printf("(%d) C time for %d pairs: %lfs\n",
+                a[ARRAYSIZE/2].a, ARRAYSIZE, time);
+
+        return 0;
+}