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+// 1695. Maximum Erasure Value
+#include "leetcode.h"
+
+/*
+ * you are given an array of posiive integers 'nums' and want to erase a
+ * subarray containing unique elements. the score you get by erasing the
+ * subarray is equal to the sum of its elements. return the maximum score you
+ * can get by erasing exactly one subarray. an array 'b' is called to be a
+ * subarray of 'a' if it forms a contiguous subsequence of 'a' that is if it is
+ * equal to 'a[l], a[l + 1], ..., a[r]' for some '(l, r)'
+ */
+
+static u_char vis[1250];
+
+bool test(int a) { return vis[a >> 3] & (1 << (a & 7)) ? true : false; }
+
+void set(int a) { vis[a >> 3] |= 1 << (a & 7); }
+
+void reset(int a) { vis[a >> 3] &= ~(1 << (a & 7)); }
+
+int maximumUniqueSubarray(int *nums, int numsSize) {
+ int ans = 0, sum = 0;
+ memset(vis, 0, sizeof(vis));
+ for (int i = 0, j = 0; i < numsSize; i++) {
+ while (test(nums[i] - 1)) {
+ sum -= nums[j];
+ reset(nums[j++] - 1);
+ }
+ sum += nums[i];
+ set(nums[i] - 1);
+ ans = fmax(ans, sum);
+ }
+ return ans;
+}
+
+int main() {
+ int n1[] = {4, 2, 4, 5, 6}, n2[] = {5, 2, 1, 2, 5, 2, 1, 2, 5};
+ printf("%d\n", maximumUniqueSubarray(n1, ARRAY_SIZE(n1))); // expect: 17
+ printf("%d\n", maximumUniqueSubarray(n2, ARRAY_SIZE(n2))); // expect: 8
+}