BZOJ 3514: Codechef MARCH14 GERALD07加强版

#include <cstdio>

inline int nextChar(void) {
  static const int siz = 1 << 20;
  static char buf[siz];
  static char *hd = buf + siz;
  static char *tl = buf + siz;
  if (hd == tl)
    fread(hd = buf, 1, siz, stdin);
  return int(*hd++);
}

inline int nextInt(void) {
  register int ret = 0;
  register int neg = false;
  register int bit = nextChar();
  for (; bit < 48; bit = nextChar())
    if (bit == ‘-‘)neg ^= true;
  for (; bit > 47; bit = nextChar())
    ret = ret * 10 + bit - ‘0‘;
  return neg ? -ret : ret;
}

template <class T>
inline void Swap(T &a, T &b) {
  T c;
  c = a;
  a = b;
  b = c;
}

template <class T>
inline T Max(const T &a, const T &b) {
  return a > b ? a : b;
}

template <class T>
inline T Min(const T &a, const T &b) {
  return a < b ? a : b;
}

const int mxn = 400005;
const int inf = 1000000007;

int n, m, q, e, ntr[mxn];

struct edge {
  int x, y;
}E[mxn];

namespace LCT {
  int top = 0;
  int stk[mxn];
  int val[mxn];
  int rev[mxn];
  int min[mxn];
  int fat[mxn];
  int son[mxn][2];

  inline bool isroot(int t) {
    int f = fat[t];
    if (!f)return true;
    if (son[f][0] == t)return false;
    if (son[f][1] == t)return false;
    return true;
  }

  inline void update(int t) {
    min[t] = val[t];
    if (son[t][0])min[t] = Min(min[t], min[son[t][0]]);
    if (son[t][1])min[t] = Min(min[t], min[son[t][1]]);
  }

  inline void push(int t) {
    rev[t] = 0;
    Swap(son[t][0], son[t][1]);
    if (son[t][0])rev[son[t][0]] ^= 1;
    if (son[t][1])rev[son[t][1]] ^= 1;
  }

  inline void pushdown(int t) {
    for (stk[++top] = t; t; )
      stk[++top] = t = fat[t];
    for (; top; --top)
      if (rev[stk[top]])
      	push(stk[top]);
  }

  inline void connect(int t, int f, int s) {
    if (t)fat[t] = f;
    if (f)son[f][s] = t;
  }

  inline void rotate(int t) {
    int f = fat[t];
    int g = fat[f];
    int s = son[f][1] == t;
    connect(son[t][!s], f, s);
    connect(f, t, !s);
    fat[t] = g;
    if (g && son[g][0] == f)son[g][0] = t;
    if (g && son[g][1] == f)son[g][1] = t;
    update(f);
    update(t);
  }

  inline void splay(int t) {
    pushdown(t);
    while (!isroot(t)) {
      int f = fat[t];
      int g = fat[f];
      if (isroot(f))
	      rotate(t);
      else {
	      int a = f && son[f][1] == t;
	      int b = g && son[g][1] == f;
	      if (a == b)
	        rotate(f), rotate(t);
	      else
	        rotate(t), rotate(t);
      }
    }
  }

  inline void access(int t) {
    for (int p = 0; t; p = t, t = fat[t])
      splay(t), son[t][1] = p, update(t);
  }

  inline void makeroot(int t) {
    access(t), splay(t), rev[t] ^= 1;
  }

  inline int find(int t) {
    access(t), splay(t);
    while (son[t][0])
      t = son[t][0];
    return t;
  }

  inline void link(int t, int f) {
    makeroot(t), fat[t] = f;
  }

  inline void cut(int a, int b) {
    makeroot(a), access(b), splay(b);
    if (son[b][0] == a)
      son[b][0] = fat[a] = 0, update(b);
  }

  inline void preworkNTR(void) {
    for (int i = 1; i <= n; ++i)
      val[i] = min[i] = inf;
    for (int i = 1; i <= m; ++i) {
      if (E[i].x == E[i].y) {
        ntr[i] = m;
        continue;
      }
      if (find(E[i].x) == find(E[i].y)) {
	      makeroot(E[i].x);
	      access(E[i].y);
	      splay(E[i].y);
	      ntr[i] = min[E[i].y];
	      cut(E[ntr[i]].x, ntr[i] + n);
	      cut(E[ntr[i]].y, ntr[i] + n);
      }
      val[i + n] = min[i + n] = i;
      link(E[i].x, i + n);
      link(E[i].y, i + n);
    }
  }
}

namespace CMT {
  const int K = 25;

  int tot = 0;
  int sum[K * mxn];
  int lsn[K * mxn];
  int rsn[K * mxn];
  int rot[K * mxn];

  void insert(int &t, int p, int l, int r, int v) {
    t = ++tot;
    lsn[t] = lsn[p];
    rsn[t] = rsn[p];
    sum[t] = sum[p] + 1;
    if (l == r)return;
    int mid = (l + r) >> 1;
    if (v <= mid)
      insert(lsn[t], lsn[p], l, mid, v);
    else
      insert(rsn[t], rsn[p], mid + 1, r, v);
  }

  int query(int t, int l, int r, int x, int y) {
    if (!t)return 0;
    if (l == x && r == y)
      return sum[t];
    int mid = (l + r) >> 1;
    if (y <= mid)
      return query(lsn[t], l, mid, x, y);
    else if (x > mid)
      return query(rsn[t], mid + 1, r, x, y);
    else
      return query(lsn[t], l, mid, x, mid) + query(rsn[t], mid + 1, r, mid + 1, y);
  }
  
  inline void preworkNTR(void) {
    for (int i = 1; i <= m; ++i)
      insert(rot[i], rot[i - 1], 0, m, ntr[i]);
  }

  inline int solve(int l, int r) {
    return n - query(rot[r], 0, m, 0, l - 1) + query(rot[l - 1], 0, m, 0, l - 1);
  }
}

signed main(void) {
  n = nextInt();
  m = nextInt();
  q = nextInt();
  e = nextInt();
  for (int i = 1; i <= m; ++i)
    E[i].x = nextInt(),
    E[i].y = nextInt();
  LCT::preworkNTR(); 
  CMT::preworkNTR();
  int lastans = 0;
  for (int i = 1; i <= q; ++i) {
    int L = nextInt();
    int R = nextInt();
    if (e)
      L ^= lastans,
      R ^= lastans;
    printf("%d\n", lastans = CMT::solve(L, R));
  }
}