2020牛客多校第五场H-Interval
https://ac.nowcoder.com/acm/contest/5670/H
题意
给出一个序列,q次询问,每次询问\([l,r]\)区间内,子区间与有多少种结果
题解
对于固定的右端点,不同的值最多只有log种,把这些值找出来,然后就是查询区间内数的种数的主席树裸题了
代码
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
struct READ {
inline char read() {
#ifdef _WIN32
return getchar();
#endif
static const int IN_LEN = 1 << 18 | 1;
static char buf[IN_LEN], *s, *t;
return (s == t) && (t = (s = buf) + fread(buf, 1, IN_LEN, stdin)), s == t ? -1 : *s++;
}
template <typename _Tp> inline READ & operator >> (_Tp&x) {
static char c11, boo;
for(c11 = read(),boo = 0; !isdigit(c11); c11 = read()) {
if(c11 == -1) return *this;
boo |= c11 == '-';
}
for(x = 0; isdigit(c11); c11 = read()) x = x * 10 + (c11 ^ '0');
boo && (x = -x);
return *this;
}
} in;
const int N = 1e5 + 50;
int L[N * 300], R[N * 300], T[N];
int sum[N * 300];
int cnt;
int update(int pre, int l, int r, int x, int v) {
int rt = ++cnt;
int mid = (l + r) >> 1;
L[rt] = L[pre], R[rt] = R[pre], sum[rt] = sum[pre] + v;
if (l < r) {
if (x <= mid) L[rt] = update(L[pre], l, mid, x, v);
else R[rt] = update(R[pre], mid + 1, r, x, v);
}
return rt;
}
int querysum(int rt, int l, int r, int ql, int qr) {
if (ql <= l && r <= qr) return sum[rt];
int mid = (l + r) >> 1;
int ans = 0;
if (ql <= mid) ans += querysum(L[rt], l, mid, ql, qr);
if (qr > mid) ans += querysum(R[rt], mid + 1, r, ql, qr);
return ans;
}
int main() {
int n; in >> n;
map<int, int> mp, pos;
for (int i = 1; i <= n; i++) {
int x; in >> x;
mp[x] = i; T[i] = T[i - 1];
map<int, int> tmp;
for (auto e : mp) tmp[e.first & x] = max(tmp[e.first & x], e.second);
for (auto e : tmp) {
if (!pos.count(e.first)) {
T[i] = update(T[i], 1, n, e.second, 1);
}
else {
T[i] = update(T[i], 1, n, e.second, 1);
T[i] = update(T[i], 1, n, pos[e.first], -1);
}
pos[e.first] = e.second;
}
mp = tmp;
}
int q; in >> q;
int ans = 0;
while (q--) {
int l, r; in >> l >> r;
l = (l ^ ans) % n + 1;
r = (r ^ ans) % n + 1;
if (l > r) swap(l, r);
printf("%d\n", ans = querysum(T[r], 1, n, l, r));
}
return 0;
}