[BZOJ3514]Codechef MARCH14 GERALD07加强版

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

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 200010
#define maxm 200010
#define maxnode 500010
#define oo 2147483647

struct Node {
	int val, mnv;
	bool rev;
	Node(): rev(0) {}
	Node(int _): val(_) {}
} ns[maxnode];
int fa[maxnode], ch[maxnode][2], S[maxn], top;
bool isrt(int u) { return !fa[u] || (ch[fa[u]][0] != u && ch[fa[u]][1] != u); }
void maintain(int o) {
	ns[o].mnv = ns[o].val;
	for(int i = 0; i < 2; i++) if(ch[o][i])
		ns[o].mnv = min(ns[o].mnv, ns[ch[o][i]].mnv);
	return ;
}
void pushdown(int o) {
	if(!ns[o].rev) return ;
	swap(ch[o][0], ch[o][1]);
	for(int i = 0; i < 2; i++) if(ch[o][i])
		ns[ch[o][i]].rev ^= 1;
	ns[o].rev = 0;
	return ;
}
void rotate(int u) {
	int y = fa[u], z = fa[y], l = 0, r = 1;
	if(!isrt(y)) ch[z][ch[z][1]==y] = u;
	if(ch[y][1] == u) swap(l, r);
	fa[u] = z; fa[y] = u; fa[ch[u][r]] = y;
	ch[y][l] = ch[u][r]; ch[u][r] = y;
	maintain(y); maintain(u);
	return ;
}
void splay(int u) {
	int t = u; S[top = 1] = t;
	while(!isrt(t)) S[++top] = fa[t], t = fa[t];
	while(top) pushdown(S[top--]);
	while(!isrt(u)) {
		int y = fa[u], z = fa[y];
		if(!isrt(y)) {
			if(ch[y][0] == u ^ ch[z][0] == y) rotate(u);
			else rotate(y);
		}
		rotate(u);
	}
	return ;
}
void access(int u) {
	splay(u); ch[u][1] = 0; maintain(u);
	while(fa[u]) splay(fa[u]), ch[fa[u]][1] = u, maintain(fa[u]), splay(u);
	return ;
}
void makeroot(int u) {
	access(u); ns[u].rev ^= 1;
	return ;
}
void link(int a, int b) {
	makeroot(b); fa[b] = a;
	return ;
}
void cut(int a, int b) {
	makeroot(a); access(b); ch[b][0] = fa[a] = 0; maintain(b);
	return ;
}
int _mnv;
void query(int a, int b) {
	makeroot(a); access(b); _mnv = ns[b].mnv;
	return ;
}

struct Edge {
	int u, v;
	Edge() {}
	Edge(int _, int __): u(_), v(__) {}
} es[maxm];

int pa[maxn];
int findset(int x) { return x == pa[x] ? x : pa[x] = findset(pa[x]); }

#define maxNode 14400010
int pre[maxm], rt[maxm];
int ToT, sumv[maxNode], lc[maxNode], rc[maxNode];
void update(int& y, int x, int l, int r, int p) {
	sumv[y = ++ToT] = sumv[x] + 1;
	if(l == r) return ;
	int mid = l + r >> 1; lc[y] = lc[x]; rc[y] = rc[x];
	if(p <= mid) update(lc[y], lc[x], l, mid, p);
	else update(rc[y], rc[x], mid + 1, r, p);
	return ;
}
int query(int o, int l, int r, int qr) {
	if(!o) return 0;
	if(r <= qr) return sumv[o];
	int mid = l + r >> 1, ans = query(lc[o], l, mid, qr);
	if(qr > mid) ans += query(rc[o], mid + 1, r, qr);
	return ans;
}

int main() {
	int n = read(), m = read(), q = read(), tp = read();
	for(int i = 1; i <= n; i++) ns[i] = Node(oo), maintain(i), pa[i] = i;
	for(int i = 1; i <= m; i++) {
		int u = read(), v = read();
		if(u == v){ pre[i] = i; continue; }
		es[i] = Edge(u, v);
		ns[i+n] = Node(i); maintain(i + n);
		int U = findset(u), V = findset(v);
		if(U == V) {
			query(u, v);
			pre[i] = _mnv;
			cut(es[_mnv].u, _mnv + n); cut(_mnv + n, es[_mnv].v);
			link(u, i + n); link(i + n, v);
		}
		else {
			pa[V] = U;
			pre[i] = 0;
			link(u, i + n); link(i + n, v);
		}
	}
	
	for(int i = 1; i <= m; i++) update(rt[i], rt[i-1], 0, m, pre[i]);
	int lst = 0;
	while(q--) {
		int l = read() ^ lst * tp, r = read() ^ lst * tp;
		printf("%d\n", lst = n - (query(rt[r], 0, m, l - 1) - query(rt[l-1], 0, m, l - 1)));
	}
	
	return 0;
}