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authorJack Sangdahl <[email protected]>2024-10-17 19:11:55 -0600
committerJack Sangdahl <[email protected]>2024-10-17 19:11:55 -0600
commitdbd535bd9e0d0803402c944cd40e33229dd9a0c1 (patch)
tree4072ab3f1ef81444970a7fdbef62bd7cae96144d
parentc65e70966f48d5b5b6ad4be8912cb0054b9b2978 (diff)
downloadleetcode-dbd535bd9e0d0803402c944cd40e33229dd9a0c1.tar.gz
leetcode-dbd535bd9e0d0803402c944cd40e33229dd9a0c1.zip
2044. count number of maximum bitwise-or subsets
-rw-r--r--count_num_max_or_subset.c43
-rw-r--r--count_num_max_or_subset.py32
2 files changed, 75 insertions, 0 deletions
diff --git a/count_num_max_or_subset.c b/count_num_max_or_subset.c
new file mode 100644
index 0000000..1b5a160
--- /dev/null
+++ b/count_num_max_or_subset.c
@@ -0,0 +1,43 @@
+// 2044. Count Number of Maximum Bitwise-OR Subsets
+#include "leetcode.h"
+
+/*
+ * given an integer array 'nums', find the maximum possible bitwise OR of a
+ * subset of 'nums' and return the number of different non-empty subsets with
+ * the maximum bitwise OR. an array 'a' is a subset of an array 'b' if 'a' can
+ * be obtained from 'b' by deleting some (possibly 0) elements of 'b'. two
+ * subsets are considered different if the indices of the elements chosen are
+ * different. the bitwose OR of an array 'a' is equal to 'a[0] | a[1] | ... |
+ * a[n]' (0-indexed)
+ */
+
+void backtrack(int *nums, int numsSize, int target, int idx, int pos,
+ int *res) {
+ if (pos == numsSize)
+ return;
+ for (int i = pos; i < numsSize; i++) {
+ int tmp = idx | nums[i];
+ if (tmp == target)
+ (*res)++;
+ backtrack(nums, numsSize, target, tmp, i + 1, res);
+ }
+}
+
+int countMaxOrSubsets(int *nums, int numsSize) {
+ int max = 0, ans = 0;
+ for (int i = 0; i < numsSize; i++)
+ max |= nums[i];
+ for (int i = 0; i < numsSize; i++) {
+ if (nums[i] == max)
+ ans++;
+ backtrack(nums, numsSize, max, nums[i], i + 1, &ans);
+ }
+ return ans;
+}
+
+int main() {
+ int n1[] = {3, 1}, n2[] = {2, 2, 2}, n3[] = {3, 2, 1, 5};
+ printf("%d\n", countMaxOrSubsets(n1, ARRAY_SIZE(n1))); // expect: 2
+ printf("%d\n", countMaxOrSubsets(n2, ARRAY_SIZE(n2))); // expect: 7
+ printf("%d\n", countMaxOrSubsets(n3, ARRAY_SIZE(n3))); // expect: 6
+}
diff --git a/count_num_max_or_subset.py b/count_num_max_or_subset.py
new file mode 100644
index 0000000..02aa433
--- /dev/null
+++ b/count_num_max_or_subset.py
@@ -0,0 +1,32 @@
+# 2044. Count Number of Maximum Bitwise-OR Subsets
+from collections import Counter
+
+"""
+given an integer array 'nums', find the maximum possible bitwise OR of a
+subset of 'nums' and return the number of different non-empty subsets with
+the maximum bitwise OR. an array 'a' is a subset of an array 'b' if 'a' can
+be obtained from 'b' by deleting some (possibly 0) elements of 'b'. two
+subsets are considered different if the indices of the elements chosen are
+different. the bitwose OR of an array 'a' is equal to 'a[0] | a[1] | ... |
+a[n]' (0-indexed)
+"""
+
+
+class Solution(object):
+ def countMaxOrSubsets(self, nums):
+ """
+ :type nums: List[int]
+ :rtype: int
+ """
+ dp = Counter([0])
+ for n in nums:
+ for i, j in list(dp.items()):
+ dp[i | n] += j
+ return dp[max(dp)]
+
+
+if __name__ == "__main__":
+ obj = Solution()
+ print(obj.countMaxOrSubsets([3, 1]))
+ print(obj.countMaxOrSubsets([2, 2, 2]))
+ print(obj.countMaxOrSubsets([3, 2, 1, 5]))