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#include "leetcode.h"
class maxBit {
public:
vector<int> bit;
maxBit(int size) { bit.resize(size + 1); }
int get(int idx) {
int ans = 0;
for (; idx > 0; idx -= idx & -idx)
ans = max(ans, bit[idx]);
return ans;
}
void update(int idx, int val) {
for (; idx < bit.size(); idx += idx & -idx)
bit[idx] = max(bit[idx], val);
}
};
class Solution {
public:
int lengthOisLIS(vector<int> &nums) {
int uniqueNum = compress(nums);
maxBit bit(uniqueNum);
for (int x : nums) {
int subLongest = bit.get(x - 1);
bit.update(x, subLongest + 1);
}
return bit.get(uniqueNum);
}
private:
int compress(vector<int> &arr) {
vector<int> uniqueSorted(arr);
sort(uniqueSorted.begin(), uniqueSorted.end());
uniqueSorted.erase(unique(uniqueSorted.begin(), uniqueSorted.end()),
uniqueSorted.end());
for (int &x : arr)
x = lower_bound(uniqueSorted.begin(), uniqueSorted.end(), x) -
uniqueSorted.begin() + 1;
return uniqueSorted.size();
}
};
int main() {
Solution obj;
vector<int> nums = {10, 9, 2, 5, 3, 7, 101, 18};
cout << obj.lengthOisLIS(nums);
}
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