#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];
static inline void pushLazy(int nod, int l, int r) {
val[nod] -= lazy[nod];
if(l < r) {
lazy[2 * nod] += lazy[nod];
lazy[2 * nod + 1] += lazy[nod];
}
lazy[nod] = 0;
}
void init(int l, int r, int nod = 1) {
if(l == r)
val[nod] = 0, fr[nod] = 1;
else {
int mid = (l + r) / 2;
init(l, mid, 2 * nod);
init(mid + 1, r, 2 * nod);
if(val[2 * nod] < val[2 * nod + 1])
val[nod] = val[2 * nod], fr[nod] = fr[2 * nod];
else if(val[2 * nod + 1] < val[2 * nod])
val[nod] = val[2 * nod + 1], fr[nod] = fr[2 * nod + 1];
else
val[nod] = val[2 * nod], fr[nod] = fr[2 * nod] + fr[2 * nod + 1];
}
}
void update(int i, int j, int valU, int l, int r, int nod = 1) {
pushLazy(nod, l, r);
if(r < i || j < l || j < i || r < l)
return;
int mid = (l + r) / 2;
if(i <= l && r <= j) {
lazy[nod] += valU;
pushLazy(nod, l, r);
} else {
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];
}
}
pair<int, int> query(int i, int j, int l, int r, int nod = 1) {
pushLazy(nod, l, r);
if(j < i || r < i || j < l || r < l)
return make_pair(MAX_N + 1, 0);
int mid = (l + r) / 2;
if(i <= l && r <= j)
return make_pair(val[nod], fr[nod]);
else {
pair<int, int> r1 = query(i, j, l, mid, 2 * nod),
r2 = query(i, j, mid + 1, r, 2 * nod + 1);
if(r2.first < r1.first)
r1 = r2;
else if(r2.first == r1.first)
r1.second += r2.second;
return r1;
}
}
int N;
int cells[4];
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);
update(cells[2], cells[3] - 1, 4 * x, 0, N);
}
static inline void activateCells(int l, int c, int x) {
activateSqr(l, c, x);
activateSqr(l - 1, c, x);
activateSqr(l, c - 1, x);
activateSqr(l - 1, c - 1, x);
}
void give_initial_chart(int H, int W, std::vector<int> _R, std::vector<int> _C) {
N = H * W;
init(0, N, 1);
R = _R;
C = _C;
matr = new int*[1 + H + 1];
for(int i = 0; i <= H + 1; ++i) {
matr[i] = new int[1 + W + 1];
for(int j = 0; j <= W + 1; ++j)
matr[i][j] = 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)
activateSqr(i, j, 1);
}
int swap_seats(int a, int b) {
activateCells(R[a], C[a], -1);
activateCells(R[b], C[b], -1);
swap(R[a], R[b]);
swap(C[a], C[b]);
swap(matr[R[a]][C[a]], matr[R[b]][C[b]]);
activateCells(R[a], C[a], 1);
activateCells(R[b], C[b], 1);
pair<int, int> x = query(0, N - 1, 0, N);
if(x.first != 4)
return 0;
return x.second;
}
