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https://git.sb/baoshuo/OI-codes.git
synced 2024-11-30 20:36:26 +00:00
65 lines
1.2 KiB
C++
65 lines
1.2 KiB
C++
#include <bits/stdc++.h>
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using namespace std;
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struct node {
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int l, r;
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string s;
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node() {
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l = r = 0;
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s = "";
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}
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node(int _l, int _r) {
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l = _l;
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r = _r;
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s = "";
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}
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} tr[50005 << 2];
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int n, m, x, y;
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string a[50005], b[50005];
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map<string, string> m1;
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void pushup(int u) {
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tr[u].s = max(tr[u << 1].s, tr[u << 1 | 1].s);
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}
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void build(int u, int l, int r) {
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tr[u] = node(l, r);
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if (l == r) {
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tr[u].s = a[l];
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return;
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}
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int mid = l + r >> 1;
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build(u << 1, l, mid);
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build(u << 1 | 1, mid + 1, r);
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pushup(u);
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}
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string query(int u, int l, int r) {
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if (l <= tr[u].l && tr[u].r <= r) {
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return tr[u].s;
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}
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int mid = tr[u].l + tr[u].r >> 1;
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string s;
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if (l <= mid) s = max(s, query(u << 1, l, r));
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if (r > mid) s = max(s, query(u << 1 | 1, l, r));
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return s;
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}
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int main() {
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cin >> n >> m;
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for (int i = 1; i <= n; i++) {
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cin >> b[i];
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for (char c : b[i]) {
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a[i].push_back(tolower(c));
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}
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m1[a[i]] = b[i];
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}
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build(1, 1, n);
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for (int i = 0; i < m; i++) {
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cin >> x >> y;
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cout << m1[query(1, x, y)] << endl;
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}
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return 0;
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} |