leetcode

commit 45170406deedd920af6ebe88b0e309f255d52c37
parent 1af9cba05269900677e23e3bbfedd3b7075e6d30
Author: Jack Sangdahl <jack@pngu.org>
Date:   Fri,  7 Nov 2025 21:29:03 -0700

1611. minimum one bit operations to make integers zero

Diffstat:
M
min_one_bit_op_zero.c
 | 
22
+++++++++++-----------

1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/min_one_bit_op_zero.c b/min_one_bit_op_zero.c
@@ -10,20 +10,20 @@
  */
 
 int minimumOneBitOperations(int n) {
-  int tmp = n, sign = 1, cnt = 0, pos = 0;
-  while (tmp) {
-    if (tmp & (1 << pos)) {
-      cnt += sign * ((1 << (pos + 1)) - 1);
-      tmp &= ~(1 << pos);
-      sign *= -1;
+  if (!n)
+    return 0;
+  int acc = 0, sign = 1;
+  int highest = 31 - __builtin_clz(n);
+  for (int i = highest; i >= 0; --i) {
+    if ((n >> i) & 1) {
+      acc += sign * ((1 << (i + 1)) - 1);
+      sign = -sign;
     }
-    pos--;
   }
-  return cnt;
+  return acc;
 }
 
 int main() {
-  printf("%d\n", minimumOneBitOperations(3));    // expect: 2
-  printf("%d\n", minimumOneBitOperations(6));    // expect: 4
-  printf("%d\n", minimumOneBitOperations(8174)); // expect: N/A
+  printf("%d\n", minimumOneBitOperations(3)); // expect: 2
+  printf("%d\n", minimumOneBitOperations(6)); // expect: 4
 }