leetcode

commit b1b4bfa3a2c70bf364080ccf0e0014cd6ae80054
parent c7a993946c13641bd0faadce68e2156e94a92e14
Author: Jack Sangdahl <jack@pngu.org>
Date:   Wed, 17 Dec 2025 09:49:41 -0700

1009. complement of base 10 integer

Diffstat:
A
complement_base_10_int.c
 | 
21
+++++++++++++++++++++
A
complement_base_10_int.py
 | 
26
++++++++++++++++++++++++++

2 files changed, 47 insertions(+), 0 deletions(-)
diff --git a/complement_base_10_int.c b/complement_base_10_int.c
@@ -0,0 +1,21 @@
+// 1009. Complement of Base 10 Integer
+#include "leetcode.h"
+
+/*
+ * the complement of an integer is the integer you get when you flip all the 0's
+ * to 1's and all the 1's to 0's in its binary representation. given an integer
+ * 'n', return its complement.
+ */
+
+int bitwiseComplement(int n) {
+  int c = 1;
+  while (c < n)
+    c = (c << 1) + 1;
+  return n ^ c;
+}
+
+int main() {
+  printf("%d\n", bitwiseComplement(5));  // expect: 2
+  printf("%d\n", bitwiseComplement(7));  // expect: 0
+  printf("%d\n", bitwiseComplement(10)); // expect: 5
+}
diff --git a/complement_base_10_int.py b/complement_base_10_int.py
@@ -0,0 +1,26 @@
+# 1009. Complement of Base 10 Integer
+
+"""
+the complement of an integer is the integer you get when you flip all the 0's
+to 1's and all the 1's to 0's in its binary representation. given an integer
+'n', return its complement.
+"""
+
+
+class Solution(object):
+    def bitwiseComplement(self, n):
+        """
+        :type n: int
+        :rtype: int
+        """
+        c = 1
+        while n > c:
+            c = c * 2 + 1
+        return c - n
+
+
+if __name__ == "__main__":
+    obj = Solution()
+    print(obj.bitwiseComplement(n=5))
+    print(obj.bitwiseComplement(n=7))
+    print(obj.bitwiseComplement(n=10))