#pragma GCC target("avx,avx2,sse,sse2")
#pragma GCC optimize("Ofast")
#include "seats.h"
#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 1000000;
int val[1+4*MAX_N], fr[1+4*MAX_N];
int lazy[1+4*MAX_N];
int initsum[MAX_N+1];
static inline void pushLazy(int nod, int l, int r) {
if(lazy[nod] != 0) {
val[nod] += lazy[nod];
if(l < r) {
lazy[2 * nod] += lazy[nod];
lazy[2 * nod + 1] += lazy[nod];
}
lazy[nod] = 0;
}
}
inline void init(int l, int r, int nod = 1) {
if(l == r) {
val[nod] = initsum[l];
fr[nod] = 1;
}
else if(l < r){
int mid = (l + r) / 2;
init(l, mid, 2 * nod);
init(mid + 1, r, 2 * nod + 1);
val[nod] = min(val[2 * nod], val[2 * nod + 1]);
if(val[2 * nod] == val[nod])
fr[nod] += fr[2 * nod];
if(val[2 * nod + 1] == val[nod])
fr[nod] += fr[2 * nod + 1];
}
}
inline void update(int i, int j, int valU, int l, int r, int nod = 1) {
pushLazy(nod, l, r);
if(r < i || j < l)
return;
int mid = (l + r) / 2;
if(i <= l && r <= j) {
lazy[nod] += valU;
pushLazy(nod, l, r);
return;
}
update(i, j, valU, l, mid, 2 * nod);
update(i, j, valU, mid + 1, r, 2 * nod + 1);
val[nod] = val[2 * nod], fr[nod] = fr[2 * nod];
if(val[2 * nod + 1] < val[nod]) {
val[nod] = val[2 * nod + 1];
fr[nod] = fr[2 * nod + 1];
} else if(val[nod] == val[2 * nod + 1])
fr[nod] += fr[2 * nod + 1];
}
int N, H, W;
int cells[4];
vector<vector<int> > matr;
vector<int> R, C;
static inline void activateSqr(int l, int c, int x) {
cells[0] = matr[l][c];
cells[1] = matr[l + 1][c];
cells[2] = matr[l][c + 1];
cells[3] = matr[l + 1][c + 1];
std::sort(cells, cells + 4);
update(cells[0], cells[1] - 1, x, 0, N - 1);
update(cells[2], cells[3] - 1, 4 * x, 0, N - 1);
}
void give_initial_chart(int H, int W, std::vector<int> _R, std::vector<int> _C) {
N = H * W;
R = _R;
C = _C;
matr.resize(H+2, vector<int>(W+2, N));
for(int i = 0; i < N; ++i) {
R[i]++;
C[i]++;
matr[R[i]][C[i]] = i;
}
for(int i = 0; i <= H; ++i)
for(int j = 0; j <= W; ++j) {
cells[0] = matr[i][j];
cells[1] = matr[i + 1][j];
cells[2] = matr[i][j + 1];
cells[3] = matr[i + 1][j + 1];
std::sort(cells, cells + 4);
initsum[cells[0]]++;
initsum[cells[1]]--;
initsum[cells[2]]+=4;
initsum[cells[3]]-=4;
}
for(int i = 1; i < N; ++i)
initsum[i] += initsum[i - 1];
init(0, N - 1, 1);
}
int dr[] = {0,-1, 0, -1};
int dc[] = {0, 0,-1, -1};
int swap_seats(int a, int b) {
vector<pair<int, int> > yeet;
for(int i = 0; i < 4; ++i) {
yeet.push_back(make_pair(R[a] + dr[i], C[a] + dc[i]));
yeet.push_back(make_pair(R[b] + dr[i], C[b] + dc[i]));
}
std::sort(yeet.begin(), yeet.end());
yeet.resize(unique(yeet.begin(), yeet.end()) - yeet.begin());
for(int i = 0; i < yeet.size(); ++i)
activateSqr(yeet[i].first, yeet[i].second, -1);
swap(R[a], R[b]);
swap(C[a], C[b]);
swap(matr[R[a]][C[a]], matr[R[b]][C[b]]);
for(int i = 0; i < yeet.size(); ++i)
activateSqr(yeet[i].first, yeet[i].second, 1);
if(val[1] != 4)
return 0;
return fr[1];
}
