// 3097. Shortest Subarray With OR at Least K II #include "leetcode.h" /* * you are given an array 'nums' of non-negative integers and an integer 'k'. an * array is called special if the bitwise OR of all its elements is at least * 'k'. return the length of the shortest special non-empty subarray of 'nums', * or return -1 if no special subarray exists. */ int minimumSubarrayLength(int *nums, int numsSize, int k) { int cnt[30] = {}, curr = 0, ans = INT_MAX; for (int i = 0, j = 0; i < numsSize; ++i) { for (int b = 0; b < 30; ++b) if ((1 << b) & nums[i]) if (++cnt[b] == 1) curr += (1 << b); while (curr >= k && j <= i) { ans = fmin(ans, i - j + 1); for (int b = 0; b < 30; ++b) if ((1 << b) & nums[j]) if (!(--cnt[b])) curr -= (1 << b); ++j; } } return ans == INT_MAX ? -1 : ans; } int main() { int n1[] = {1, 2, 3}, n2[] = {2, 1, 8}, n3[] = {1, 2}; printf("%d\n", minimumSubarrayLength(n1, ARRAY_SIZE(n1), 2)); // expect: 1 printf("%d\n", minimumSubarrayLength(n2, ARRAY_SIZE(n2), 10)); // expect: 3 printf("%d\n", minimumSubarrayLength(n3, ARRAY_SIZE(n3), 0)); // expect: 1 }