#include "seats.h"
#include <bits/stdc++.h>
using namespace std;
const int maxN = 1e6 + 20;
pair<int, int> tree[maxN * 4];
int lazy[maxN * 4];
int R[maxN];
int C[maxN];
vector<vector<int>> seats;
int N;
void build_tree(int id, int lt, int rt) {
if (lt == rt) {
tree[id] = make_pair(0, 1);
return;
}
int mt = (lt + rt) >> 1;
build_tree(id << 1, lt, mt);
build_tree(id << 1 | 1, mt + 1, rt);
tree[id] = make_pair(0, rt - lt + 1);
}
void update_tree(int id, int lt, int rt, int ql, int qr, int add) {
if (lt == ql && rt == qr) {
tree[id].first += add;
lazy[id] += add;
return;
}
tree[id << 1].first += lazy[id];
lazy[id << 1] += lazy[id];
tree[id << 1 | 1].first += lazy[id];
lazy[id << 1 | 1] += lazy[id];
lazy[id] = 0;
int mt = (lt + rt) >> 1;
if (qr <= mt) {
update_tree(id << 1, lt, mt, ql, qr, add);
}
else if (ql >= mt + 1) {
update_tree(id << 1 | 1, mt + 1, rt, ql, qr, add);
}
else {
update_tree(id << 1, lt, mt, ql, mt, add);
update_tree(id << 1 | 1, mt + 1, rt, mt + 1, qr, add);
}
tree[id].first = min(tree[id << 1].first, tree[id << 1 | 1].first);
tree[id].second = (tree[id << 1].first == tree[id].first ? tree[id << 1].second : 0) + (tree[id << 1 | 1].first == tree[id].first ? tree[id << 1 | 1].second : 0);
}
void update_square(int i, int j, int add) {
vector<int> vals = {seats[i][j], seats[i][j + 1], seats[i + 1][j], seats[i + 1][j + 1]};
sort(vals.begin(), vals.end());
if (vals[0] < vals[1]) {
update_tree(1, 1, N, vals[0], vals[1] - 1, add);
}
if (vals[2] < vals[3]) {
update_tree(1, 1, N, vals[2], vals[3] - 1, add);
}
}
void update_pos(int i, int j, int val) {
update_square(i - 1, j - 1, -1);
update_square(i - 1, j, -1);
update_square(i, j - 1, -1);
update_square(i, j, -1);
seats[i][j] = val;
update_square(i - 1, j - 1, 1);
update_square(i - 1, j, 1);
update_square(i, j - 1, 1);
update_square(i, j, 1);
}
void give_initial_chart(int H, int W, vector<int> _R, vector<int> _C) {
H = H;
W = W;
N = H * W;
seats.resize(H + 2, vector<int>(W + 2, N + 1));
build_tree(1, 1, N);
for (int i = 1; i <= N; i++) {
R[i] = _R[i - 1] + 1;
C[i] = _C[i - 1] + 1;
seats[R[i]][C[i]] = i;
}
for (int i = 0; i <= H; i++) {
for (int j = 0; j <= W; j++) {
update_square(i, j, 1);
}
}
}
int swap_seats(int a, int b) {
a++;
b++;
update_pos(R[a], C[a], b);
update_pos(R[b], C[b], a);
swap(R[a], R[b]);
swap(C[a], C[b]);
return tree[1].second;
}
