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https://git.sb/baoshuo/OI-codes.git
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56 lines
1.1 KiB
C++
56 lines
1.1 KiB
C++
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#include <bits/stdc++.h>
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using namespace std;
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int n, a[100005], ans;
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struct node {
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int val;
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node* next[2];
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~node() {
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for (auto i : next) {
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delete i;
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}
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}
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};
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void insert(node* root, int x, int b) {
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if (!x) {
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root->val++;
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return;
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}
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if (root->next[(x >> b) & 1] == nullptr) root->next[(x >> b) & 1] = new node();
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insert(root->next[(x >> b) & 1], x - (((x >> b) & 1) << b), b - 1);
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}
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int search(node* root, int x) {
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int res = 0;
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node* p = root;
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for (int i = 30; i >= 0; i--) {
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if (p == nullptr) break;
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if (p->next[!((x >> i) & 1)] != nullptr) {
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res += 1 << i;
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p = p->next[!((x >> i) & 1)];
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} else {
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p = p->next[(x >> i) & 1];
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}
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}
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return res;
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}
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int main() {
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node* root = new node();
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cin >> n;
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for (int i = 0; i < n; i++) {
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cin >> a[i];
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insert(root, a[i], 30);
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}
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for (int i = 0; i < n; i++) {
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ans = max(ans, search(root, a[i]));
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}
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cout << ans << endl;
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delete root;
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return 0;
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}
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