exercism

commit fb3a4e6b95eaff75f8e2952039e6367e27671e67
parent d43303ce4aaa5e21c99deaec2aa0fcde213aad75
Author: dwrz <dwrz@dwrz.net>
Date:   Mon, 22 Apr 2019 01:17:19 +0000

Refactor grains/square

Check internally for valid squares.

Shift on 1, not two -- the first bit is to mark 0 and 1, and shifting it once will turn it into 2.

Diffstat:
M
c/grains/src/grains.c
 | 
5
++---

1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/c/grains/src/grains.c b/c/grains/src/grains.c
@@ -1,9 +1,8 @@
 #include "grains.h"
 
 unsigned long long square(int n) {
-  if (!validSquare(n)) return 0;
-  if (n == 1) return 1;
-  return 2llu << (n-2);
+  if (n < 1 || n > 64) return 0;
+  return 1ull << (n-1);
 }
 
 unsigned long long total() {