#include "bits/extc++.h"
using namespace std;
template <typename T>
void dbgh(const T& t) {
cerr << t << endl;
}
template <typename T, typename... U>
void dbgh(const T& t, const U&... u) {
cerr << t << " | ";
dbgh(u...);
}
#ifdef DEBUG
#define dbg(...) \
cerr << "L" << __LINE__ << " [" << #__VA_ARGS__ << "]: "; \
dbgh(__VA_ARGS__);
#else
#define dbg(...)
#define cerr \
if (false) \
cerr
#endif
#define endl "\n"
#define long int64_t
#define sz(x) int((x).size())
struct Node {
int rmn, rmx, cmn, cmx;
int area() const {
return (rmx - rmn + 1) * (cmx - cmn + 1);
}
bool check(int i) const {
return area() == i + 1;
}
bool operator==(const Node& n) const {
return rmn == n.rmn && rmx == n.rmx && cmn == n.cmn && cmx == n.cmx;
}
bool operator!=(const Node& n) const {
return !(*this == n);
}
Node& operator+=(const Node& n) {
rmn = min(rmn, n.rmn);
rmx = max(rmx, n.rmx);
cmn = min(cmn, n.cmn);
cmx = max(cmx, n.cmx);
return *this;
}
friend Node operator+(Node a, const Node& b) {
return a += b;
}
friend ostream& operator<<(ostream& out, const Node& n) {
return out << "{" << n.rmn << ", " << n.rmx << ", " << n.cmn << ", "
<< n.cmx << "}";
}
static Node def() {
return {int(1e9), -1, int(1e9), -1};
}
static Node from(int r, int c) {
return {r, r, c, c};
}
};
struct ST {
int n;
vector<Node> arr, v;
ST() : ST(vector<Node> {}) {}
ST(const vector<Node>& arr) : n(sz(arr)), arr(arr), v(4 * n) {
if (n) {
build(1, 0, n - 1);
}
}
void build(int o, int l, int r) {
if (l == r) {
v[o] = arr[l];
return;
}
int mid = (l + r) / 2, lc = o * 2, rc = lc + 1;
build(lc, l, mid);
build(rc, mid + 1, r);
v[o] = v[lc] + v[rc];
}
void update(int o, int l, int r, int ind, const Node& x) {
if (l == r) {
v[o] = x;
return;
}
int mid = (l + r) / 2, lc = o * 2, rc = lc + 1;
if (ind <= mid) {
update(lc, l, mid, ind, x);
} else {
update(rc, mid + 1, r, ind, x);
}
v[o] = v[lc] + v[rc];
}
void update(int ind, const Node& x) {
update(1, 0, n - 1, ind, x);
}
Node query(int o, int l, int r, int ql, int qr) {
if (ql <= l && r <= qr) {
return v[o];
}
int mid = (l + r) / 2, lc = o * 2, rc = lc + 1;
if (ql <= mid) {
if (mid < qr) {
return query(lc, l, mid, ql, qr) +
query(rc, mid + 1, r, ql, qr);
}
return query(lc, l, mid, ql, qr);
}
return query(rc, mid + 1, r, ql, qr);
}
Node query(int l, int r) {
return query(1, 0, n - 1, l, r);
}
void solve(int o, int l, int r, const Node& pref, vector<int>& out) {
if (pref == pref + v[o]) {
return;
} else if (l == r) {
out.push_back((pref + v[o]).area());
return;
}
int mid = (l + r) / 2, lc = o * 2, rc = lc + 1;
solve(lc, l, mid, pref, out);
solve(rc, mid + 1, r, pref + v[lc], out);
}
int solve() {
vector<int> arr;
solve(1, 0, n - 1, Node::def(), arr);
int ans = 0;
for (auto& a : arr) {
ans += query(0, a - 1).check(a - 1);
}
return ans;
}
};
int n, m, ans;
vector<int> r, c;
vector<Node> nodes;
ST st;
void give_initial_chart(int _n, int _m, vector<int> _r, vector<int> _c) {
n = _n;
m = _m;
r = _r;
c = _c;
for (int i = 0; i < n * m; i++) {
Node cur = Node::from(r[i], c[i]);
if (!i) {
nodes.push_back(cur);
} else {
nodes.push_back(nodes.back() + cur);
}
ans += nodes[i].check(i);
}
vector<Node> arr;
for (int i = 0; i < n * m; i++) {
arr.push_back(Node::from(r[i], c[i]));
}
st = arr;
}
int swap_seats(int a, int b) {
if (a > b) {
swap(a, b);
}
swap(r[a], r[b]);
swap(c[a], c[b]);
st.update(a, Node::from(r[a], c[a]));
st.update(b, Node::from(r[b], c[b]));
if (n <= 1000 && m <= 1000) {
return st.solve();
}
for (int i = a; i <= b; i++) {
ans -= nodes[i].check(i);
Node cur = Node::from(r[i], c[i]);
if (!i) {
nodes[i] = cur;
} else {
nodes[i] = nodes[i - 1] + cur;
}
ans += nodes[i].check(i);
}
return ans;
}
