#include "seats.h"
#include <bits/stdc++.h>
using namespace std;
int H, W;
vector<int> R, C;
struct seg {
int lr, hr, lc, hc;
} tree[4000000];
seg merge(seg a, seg b) {
return {min(a.lr, b.lr), max(a.hr, b.hr), min(a.lc, b.lc), max(a.hc, b.hc)};
}
seg query(int l, int r, int cur, int lo, int hi) {
if (l == lo && r == hi) {
return tree[cur];
}
int lmid = (lo + hi) / 2, rmid = lmid + 1;
if (r <= lmid) {
return query(l, r, cur << 1 | 0, lo, lmid);
} else if(l >= rmid) {
return query(l, r, cur << 1 | 1, rmid, hi);
} else {
return merge(query(l, lmid, cur << 1 | 0, lo, lmid),
query(rmid, r, cur << 1 | 1, rmid, hi));
}
}
void update(int pos, pair<int, int> val, int cur, int lo, int hi) {
if (lo == hi) {
tree[cur] = {val.first, val.first, val.second, val.second};
} else {
int lmid = (lo + hi) / 2, rmid = lmid + 1;
if (pos <= lmid) {
update(pos, val, cur << 1 | 0, lo, lmid);
} else {
update(pos, val, cur << 1 | 1, rmid, hi);
}
tree[cur] = merge(tree[cur << 1 | 0],
tree[cur << 1 | 1]);
}
}
void give_initial_chart(int HH, int WW, vector<int> RR, vector<int> CC) {
H = HH, W = WW, R = RR, C = CC;
for (int i = 0; i < H * W; i++) {
update(i + 1, {R[i], C[i]}, 1, 1, H * W);
}
}
int swap_seats(int a, int b) {
swap(R[a], R[b]);
swap(C[a], C[b]);
update(a + 1, {R[a], C[a]}, 1, 1, H * W);
update(b + 1, {R[b], C[b]}, 1, 1, H * W);
int ans = 0, sz = 1;
while (sz <= H * W) {
seg s = query(1, sz, 1, 1, H * W);
int box = (s.hr - s.lr + 1) * (s.hc - s.lc + 1);
if (box == sz) {
ans++, sz++;
} else {
sz = box;
}
}
return ans;
}
