#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())
template <typename T, typename Op = plus<T>>
struct ST {
int n;
Op op;
vector<T> arr, v;
ST() : ST(vector<T> {}) {}
ST(const vector<T>& arr) : n(sz(arr)), op(), 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] = op(v[lc], v[rc]);
}
void update(int o, int l, int r, int ind, const T& 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);
}
}
void update(int ind, const T& x) {
update(1, 0, n - 1, ind, x);
}
T 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 op(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);
}
};
struct Mn {
int operator()(int a, int b) const {
return min(a, b);
}
};
struct Mx {
int operator()(int a, int b) const {
return max(a, b);
}
};
struct Node {
int rmn, rmx, cmn, cmx;
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;
}
bool check(int i) const {
return (rmx - rmn + 1) * (cmx - cmn + 1) == i + 1;
}
friend Node operator+(Node a, const Node& b) {
return a += b;
}
static Node from(int r, int c) {
return {r, r, c, c};
}
};
int n, m, ans;
vector<int> r, c;
vector<Node> nodes;
ST<int, Mn> rmn, cmn;
ST<int, Mx> rmx, cmx;
void give_initial_chart(int _n, int _m, vector<int> _r, vector<int> _c) {
n = _n;
m = _m;
r = _r;
c = _c;
rmn = r;
rmx = r;
cmn = c;
cmx = 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);
}
}
int swap_seats(int a, int b) {
if (a > b) {
swap(a, b);
}
swap(r[a], r[b]);
swap(c[a], c[b]);
for (int ind : {a, b}) {
rmn.update(ind, r[ind]);
rmx.update(ind, r[ind]);
cmn.update(ind, c[ind]);
cmx.update(ind, c[ind]);
}
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;
}
