// bzoj3514
#include<algorithm>
#include<iostream>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<cmath>
#define LL long long
#define lim 1000000000
#define inf 2147483640
#define Pi acos(-1.0)
#define free(a) freopen(a".in","r",stdin),freopen(a".out","w",stdout)
using namespace std;const int maxn=200010;
int n,m,Q,T,ans,rt[maxn],ntr[maxn];
struct edge {int u,v;}e[maxn];
struct node {int son[2],s,rev;int& operator [] (int x) {return son[x];}
};namespace LCT {int fa[maxn<<1];node tr[maxn<<1];void reverse(int x) {tr[x].rev^=1;swap(tr[x][0],tr[x][1]);}void pushup(int x) {tr[x].s=x<=n ? inf : x;int l=tr[x][0],r=tr[x][1];if (l) tr[x].s=min(tr[x].s,tr[l].s);if (r) tr[x].s=min(tr[x].s,tr[r].s);}void pushdown(int x) {if (tr[fa[x]][0]==x || tr[fa[x]][1]==x) pushdown(fa[x]);if (tr[x].rev) {if (tr[x][0]) reverse(tr[x][0]);if (tr[x][1]) reverse(tr[x][1]);tr[x].rev^=1;}}void rotate(int x) {int y=fa[x],z=fa[y],l,r;l=tr[y][1]==x;r=l^1;if (tr[z][0]==y || tr[z][1]==y) tr[z][tr[z][1]==y]=x;fa[x]=z;fa[y]=x;fa[tr[x][r]]=y;tr[y][l]=tr[x][r];tr[x][r]=y;pushup(y);pushup(x);}void splay(int x) {pushdown(x);while (tr[fa[x]][0]==x || tr[fa[x]][1]==x) {int y=fa[x],z=fa[y];if (tr[z][0]==y || tr[z][1]==y) {if (tr[z][0]==y ^ tr[y][0]==x) rotate(x);else rotate(y);}rotate(x);}}void access(int x) {for (int y=0;x;y=x,x=fa[x])splay(x),tr[x][1]=y,pushup(x);}void makeroot(int x) {access(x);splay(x);reverse(x);}int query(int x,int y) {makeroot(x);access(y);splay(y);return tr[y].s;}void link(int x,int y) {makeroot(x);fa[x]=y;}void cut(int x,int y) {makeroot(x);access(y);splay(y);fa[x]=tr[y][0]=0;pushup(y);}int find(int x) {return fa[x] ? find(fa[x]) : x;}void main() {for (int i=1;i<=m;i++) {scanf("%d%d",&e[i].u,&e[i].v);if (e[i].u==e[i].v) ntr[i]=i;else if (find(e[i].u)==find(e[i].v)) {int x=query(e[i].u,e[i].v);ntr[i]=x-n;cut(x,e[x-n].u);cut(x,e[x-n].v);link(i+n,e[i].u);link(i+n,e[i].v);}else ntr[i]=0,link(i+n,e[i].u),link(i+n,e[i].v);}}
}namespace Chairtree {int sz;node tr[maxn*40];void build(int &u,int v,int l,int r,int val) {if (!u) u=++sz;if (l==r) {tr[u].s=tr[v].s+1;return;}int mid=(l+r)>>1;if (val<=mid) build(tr[u][0],tr[v][0],l,mid,val),tr[u][1]=tr[v][1];else build(tr[u][1],tr[v][1],mid+1,r,val),tr[u][0]=tr[v][0];tr[u].s=tr[tr[u][0]].s+tr[tr[u][1]].s;}int query(int u,int v,int l,int r,int ql,int qr) {if (!u && !v) return 0;if (l==ql && r==qr) return tr[v].s-tr[u].s;int mid=(l+r)>>1;if (qr<=mid) return query(tr[u][0],tr[v][0],l,mid,ql,qr);else if (ql>mid) return query(tr[u][1],tr[v][1],mid+1,r,ql,qr);else return query(tr[u][0],tr[v][0],l,mid,ql,mid)+query(tr[u][1],tr[v][1],mid+1,r,mid+1,qr);}
}
using namespace Chairtree;int main() {scanf("%d%d%d%d",&n,&m,&Q,&T);LCT::main();for (int i=1;i<=m;i++) build(rt[i],rt[i-1],0,m,ntr[i]);for (int l,r,i=1;i<=Q;i++) {scanf("%d%d",&l,&r);if (T) l^=ans,r^=ans;ans=n-query(rt[l-1],rt[r],0,m,0,l-1);printf("%d\n",ans);}return 0;
}