//12252024832524
#include <bits/stdc++.h>
#define TT template<typename T>
using namespace std; 

typedef long long LL;
const int MAXN = 200005;
const int INF = 0x3f3f3f3f;
int n,m,q,ty,ans;

LL Read()
{
	LL x = 0,f = 1;char c = getchar();
	while(c > '9' || c < '0'){if(c == '-')f = -1;c = getchar();}
	while(c >= '0' && c <= '9'){x = (x*10) + (c^48);c = getchar();}
	return x * f;
}
TT void Put1(T x)
{
	if(x > 9) Put1(x/10);
	putchar(x%10^48);
}
TT void Put(T x,char c = -1)
{
	if(x < 0) putchar('-'),x = -x;
	Put1(x); if(c >= 0) putchar(c);
}
TT T Max(T x,T y){return x > y ? x : y;}
TT T Min(T x,T y){return x < y ? x : y;}
TT T Abs(T x){return x < 0 ? -x : x;}

#define lc t[x].ch[0]
#define rc t[x].ch[1]
int tot;
struct node{
	int ch[2],f,val,s;
	bool revtag;
}t[MAXN<<1]; 
bool ck(int x){return x == t[t[x].f].ch[1];}
void lk(int x,int fa,bool d){t[x].f = fa; if(fa) t[fa].ch[d] = x;}
bool isroot(int x){return x != t[t[x].f].ch[0] && x != t[t[x].f].ch[1];}
void rev(int x){if(!x) return; t[x].revtag ^= 1; swap(lc,rc);}
void up(int x){t[x].s = Min(t[lc].s,t[rc].s),t[x].s = Min(t[x].s,t[x].val);}
void down(int x){
	if(!t[x].revtag) return;
	rev(lc); rev(rc);
	t[x].revtag = 0;
}
void rotate(int x){
	int fa = t[x].f,d = ck(x);
	if(isroot(fa)) t[x].f = t[fa].f;
	else lk(x,t[fa].f,ck(fa));
	lk(t[x].ch[d^1],fa,d);
	lk(fa,x,d^1);
	up(fa); up(x);
}
void downtag(int x){
	if(!isroot(x)) downtag(t[x].f);
	down(x);
}
void splay(int x){
	downtag(x);
	for(int y = t[x].f;!isroot(x);rotate(x),y = t[x].f)
		if(!isroot(y)) rotate(ck(x) == ck(y) ? y : x);
}
void access(int x){
	for(int lst = 0; x ;lst = x,x = t[x].f)
		splay(x),rc = lst,up(x);
}
void makeroot(int x){
	access(x); splay(x); rev(x); 
}
int findroot(int x){
	access(x); splay(x); 
	while(lc) down(x),x = lc;
	splay(x); return x;
}
void split(int x,int y){
	makeroot(x); access(y); splay(y);
}
void link(int x,int y){
	makeroot(x); t[x].f = y;
}
void cut(int x,int y){
	makeroot(x); access(y); splay(x);
	t[y].f = rc = 0,up(x); 
}

//一道题两个数据结构，重名真的烦人 
int rt[MAXN],ch[MAXN*40][2],sum[MAXN*40],pt,lsttot;
void Add(int lst,int &x,int l,int r,int pos,int val){
	if(x <= lsttot) x = ++pt,ch[x][0] = ch[lst][0],ch[x][1] = ch[lst][1],sum[x] = sum[lst];
	sum[x] += val;
	if(l == r) return;
	int mid = (l+r) >> 1;
	if(pos <= mid) Add(ch[lst][0],ch[x][0],l,mid,pos,val);
	else Add(ch[lst][1],ch[x][1],mid+1,r,pos,val);
}
int Query(int x,int l,int r,int ql,int qr){
	if(!x) return 0;
	if(ql <= l && r <= qr) return sum[x];
	int mid = (l+r) >> 1,ret = 0;
	if(ql <= mid) ret += Query(ch[x][0],l,mid,ql,qr);
	if(mid+1 <= qr) ret += Query(ch[x][1],mid+1,r,ql,qr);
	return ret;
}

int E[MAXN][3],pre[MAXN];

int main()
{
//	freopen(".in","r",stdin);
//	freopen(".out","w",stdout);
	n = tot = Read(); m = Read(); q = Read(); ty = Read();
	for(int i = 0;i <= n;++ i) t[i].s = t[i].val = INF;
	for(int i = 1;i <= m;++ i){
		E[i][0] = Read(),E[i][1] = Read();
		if(E[i][0] == E[i][1]){
			pre[i] = i;
			continue;
		}
		E[i][2] = ++tot;
		t[tot].s = t[tot].val = i;
		if(findroot(E[i][0]) == findroot(E[i][1])){
			split(E[i][0],E[i][1]); int ID = t[E[i][1]].s;
			pre[i] = ID;
			cut(E[ID][0],E[ID][2]); cut(E[ID][1],E[ID][2]);
		}
		link(E[i][0],E[i][2]); link(E[i][1],E[i][2]);
	}
	for(int i = 1;i <= m;++ i) {
		lsttot = pt;
		Add(rt[i-1],rt[i],0,m,pre[i],1);
	}
	while(q --> 0){
		int l = Read()^(ty ? ans : 0),r = Read()^(ty ? ans : 0);
		Put(ans = n-(Query(rt[r],0,m,0,l-1)-Query(rt[l-1],0,m,0,l-1)),'\n');
	}
	return 0;
}