LY1099 [ 20230222 CQYC模拟赛 T2 ] 相似序列
题意
给定一个序列。
每次询问求两个区间排序后是否只有一个或者没有位置不同。
Sol
不难想到主席树维护值域。
考虑如何判断。
注意到当前答案正确,当且仅当值域上两点不同且相邻。
维护每个点的哈希值判断即可。
Code
#include <iostream>
#include <algorithm>
#include <cstdio>
#include <array>
#define int long long
using namespace std;
#ifdef ONLINE_JUDGE
#define getchar() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 21, stdin), p1 == p2) ? EOF : *p1++)
char buf[1 << 23], *p1 = buf, *p2 = buf, ubuf[1 << 23], *u = ubuf;
#endif
int read() {
int p = 0, flg = 1;
char c = getchar();
while (c < '0' || c > '9') {
if (c == '-') flg = -1;
c = getchar();
}
while (c >= '0' && c <= '9') {
p = p * 10 + c - '0';
c = getchar();
}
return p * flg;
}
void write(int x) {
if (x < 0) {
x = -x;
putchar('-');
}
if (x > 9) {
write(x / 10);
}
putchar(x % 10 + '0');
}
const int N = 1e5 + 5;
array <int, N> idx;
namespace Sgt {
array <int, N * 800> lc, rc;
array <int, N * 800> edge;
int cnt;
void pushup(int x) {
edge[x] = edge[lc[x]] + edge[rc[x]];
}
void modify(int &x, int l, int r, int y) {
cnt++;
lc[cnt] = lc[x];
rc[cnt] = rc[x];
edge[cnt] = edge[x];
x = cnt;
if (l == r) {
edge[x] += idx[y];
return;
}
int mid = (l + r) >> 1;
if (y <= mid) modify(lc[x], l, mid, y);
else modify(rc[x], mid + 1, r, y);
pushup(x);
}
int query(int x1, int x2, int l, int r, int L, int R) {
if (L > r || R < l) return 0;
if (L <= l && R >= r) return (edge[x1] - edge[x2]);
int mid = (l + r) >> 1, ans = 0;
if (L <= mid) ans += query(lc[x1], lc[x2], l, mid, L, R);
if (R > mid) ans += query(rc[x1], rc[x2], mid + 1, r, L, R);
return ans;
}
}
array <int, N> rot;
signed main() {
#ifdef ONLINE_JUDGE
freopen("similar.in", "r", stdin);
freopen("similar.out", "w", stdout);
#endif
int n = read(), q = read();
idx[0] = 1;
for (int i = 1; i <= 1e5; i++)
idx[i] = idx[i - 1] * 131ll;
for (int i = 1; i <= n; i++) {
int x = read();
rot[i] = rot[i - 1];
Sgt::modify(rot[i], 1, 1e5, x);
}
while (q--) {
int x_1 = read(), y_1 = read(), x_2 = read(), y_2 = read();
int tp1, tp2;
if ((tp1 = Sgt::query(rot[y_1], rot[x_1 - 1], 1, 1e5, 1, 1e5)) ==
(tp2 = Sgt::query(rot[y_2], rot[x_2 - 1], 1, 1e5, 1, 1e5))) {
puts("YES");
continue;
}
/* cout << tp1 << " " << (int)tp2 << endl; */
int l = 1, r = 1e5 + 1, itl = 0;
while (l <= r) {
int mid = (l + r) >> 1;
if (Sgt::query(rot[y_1], rot[x_1 - 1], 1, 1e5, 1, mid) ==
Sgt::query(rot[y_2], rot[x_2 - 1], 1, 1e5, 1, mid))
itl = mid, l = mid + 1;
else
r = mid - 1;
}
l = 1, r = 1e5 + 1;
int itr = 0;
while (l <= r) {
int mid = (l + r) >> 1;
if (Sgt::query(rot[y_1], rot[x_1 - 1], 1, 1e5, mid, 1e5) ==
Sgt::query(rot[y_2], rot[x_2 - 1], 1, 1e5, mid, 1e5))
itr = mid, r = mid - 1;
else
l = mid + 1;
}
itl += 2, itr -= 2;
/* write(itl), putchar(32); */
/* write(itr), puts(""); */
if (!Sgt::query(rot[y_1], rot[x_1 - 1], 1, 1e5, itl, itr) &&
!Sgt::query(rot[y_2], rot[x_2 - 1], 1, 1e5, itl, itr))
puts("YES");
else
puts("NO");
}
return 0;
}