NTESTS: reduce from 96 to 16

Takes 2,5 minutes anyway.

BUILD

@@ -1,9 +1,9 @@
-NTESTS=96
+NTESTS=16
 
 [
     cc_binary(
         name = "zigzag-{}".format(i),
-        srcs = ["main.c"],
+        srcs = ["main.cc"],
         copts = ["-DZIGZAG={}".format(i)],
     ) for i in range(NTESTS)
 ]

main.c

@@ -1,11 +0,0 @@
-#include <stdio.h>
-#include <features.h>
-
-int main() {
-    #ifdef __GLIBC__
-    printf("glibc_%d.%d\n", __GLIBC__, __GLIBC_MINOR__);
-    #else
-    printf("non-glibc\n");
-    #endif
-    return 0;
-}