aboutsummaryrefslogtreecommitdiff
path: root/long_nice_subarr.c
diff options
context:
space:
mode:
Diffstat (limited to 'long_nice_subarr.c')
-rw-r--r--long_nice_subarr.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/long_nice_subarr.c b/long_nice_subarr.c
new file mode 100644
index 0000000..cfa50f3
--- /dev/null
+++ b/long_nice_subarr.c
@@ -0,0 +1,53 @@
+// 2401. Longest Nice Subarray
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+/*
+ * given an array 'nums' consisting of positive integers. we call a subarray of
+ * 'nums' nice if the bitwise AND of every pair of elements that are in
+ * different positions in the subarray is equal to 0. return the length of the
+ * longest nice subarray. a subarray is contiguous part of an array. note that
+ * subarrays of length 1 are always considered nice.
+ */
+
+bool check(int *bit, int n) {
+ for (int i = 0; i < n; i++)
+ if (bit[i] > 1)
+ return false;
+ return true;
+}
+
+int longestNiceSubarray(int *nums, int nums_size) {
+ int *bit = calloc(32, sizeof(int));
+ int left = 0, right = 0;
+ while (right < nums_size) {
+ int k = nums[right], pos = 0;
+ while (k) {
+ if (k % 2 == 1)
+ bit[pos]++;
+ k /= 2;
+ pos++;
+ }
+ right++;
+ if (!check(bit, 32)) {
+ k = nums[left];
+ pos = 0;
+ while (k) {
+ if (k % 2 == 1)
+ bit[pos]--;
+ k /= 2;
+ pos++;
+ }
+ left++;
+ }
+ }
+ return right - left;
+}
+
+int main() {
+ int n1[] = {1, 3, 8, 48, 10}, ns1 = 5;
+ int n2[] = {3, 1, 5, 11, 13}, ns2 = 5;
+ printf("%d\n", longestNiceSubarray(n1, ns1)); // expect: 3
+ printf("%d\n", longestNiceSubarray(n2, ns2)); // expect: 1
+}