[BZOJ2821]作诗(Poetize)

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cctype>
#include <algorithm>
#include <vector>
#include <cmath>
using namespace std;

const int BufferSize = 1 << 16;
char buffer[BufferSize], *Head, *Tail;
inline char Getchar() {
	if(Head == Tail) {
		int l = fread(buffer, 1, BufferSize, stdin);
		Tail = (Head = buffer) + l;
	}
	return *Head++;
}
int read() {
	int x = 0, f = 1; char c = Getchar();
	while(!isdigit(c)){ if(c == ‘-‘) f = -1; c = Getchar(); }
	while(isdigit(c)){ x = x * 10 + c - ‘0‘; c = Getchar(); }
	return x * f;
}

#define maxn 100010
#define maxbl 2010

int n, A[maxn], tot[maxn];

int cb, st[maxbl], en[maxbl], even[maxbl][maxbl], blid[maxn];
vector <int> pos[maxn];

int calc(int l, int r, int col) {
	if(l > r) return 0;
	return upper_bound(pos[col].begin(), pos[col].end(), r) - lower_bound(pos[col].begin(), pos[col].end(), l);
}
int appcol[maxn], capp, clo[maxn];
int query(int ql, int qr, int tag) {
	if(blid[ql] == blid[qr]) {
		int tmp = 0;
		for(int i = ql; i <= qr; i++) {
			if(clo[A[i]] != tag) clo[A[i]] = tag, tot[A[i]] = 0;
			tot[A[i]]++;
			if((tot[A[i]] & 1) && tot[A[i]] > 1) tmp--;
			if(!(tot[A[i]] & 1)) tmp++;
		}
		return tmp;
	}
	int bl = blid[ql], br = blid[qr], tmp = even[bl+1][br-1];
	capp = 0;
	for(int i = ql; i <= en[bl]; i++) {
		if(clo[A[i]] != tag) clo[A[i]] = tag, tot[A[i]] = 0;
		if(!tot[A[i]]) appcol[++capp] = A[i];
		tot[A[i]] = 1;
	}
	for(int i = st[br]; i <= qr; i++) {
		if(clo[A[i]] != tag) clo[A[i]] = tag, tot[A[i]] = 0;
		if(!tot[A[i]]) appcol[++capp] = A[i];
		tot[A[i]] = 1;
	}
	for(int i = 1; i <= capp; i++) {
		int appt = calc(ql, qr, appcol[i]), appt_bl = calc(st[bl+1], en[br-1], appcol[i]);
		if(!(appt & 1) && ((appt_bl & 1) || !appt_bl)) tmp++;
		if((appt & 1) && (!(appt_bl & 1) && appt_bl)) tmp--;
	}
	return tmp;
}

int main() {
	n = read(); int C = read(), q = read();
	for(int i = 1; i <= n; i++) A[i] = read();
	
	int m = 50;
	for(int i = 1; i <= n; i++) {
		int bl = (i - 1) / m + 1; cb = max(cb, bl);
		blid[i] = bl;
		if(!st[bl]) st[bl] = i; en[bl] = i;
		pos[A[i]].push_back(i);
	}
	for(int i = 1; i <= cb; i++) {
		memset(tot, 0, sizeof(tot));
		int tmp = 0;
		for(int j = st[i]; j <= n; j++) {
			tot[A[j]]++;
			if((tot[A[j]] & 1) && tot[A[j]] > 1) tmp--;
			if(!(tot[A[j]] & 1)) tmp++;
			if(j == n || blid[j] != blid[j+1]) even[i][blid[j]] = tmp;
		}
	}
	
	int lstans = 0;
	while(q--) {
		int l = (read() + lstans) % n + 1, r = (read() + lstans) % n + 1;
		if(l > r) swap(l, r);
		printf("%d\n", lstans = query(l, r, q + 1));
	}
	
	return 0;
}