#include "seats.h"
#include<bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define all(x) x.begin(), x.end()
using ll = long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
template<typename T>
using matrix = vector<vector<T>>;
vector<pii> v;
int resp = 0;
vector<pii> mini, maxi;
vector<int> isgood;
int n;
struct SegTree{
struct seg{
int sum, min, minct;
};
vector<seg> tree;
int q, val, sz;
SegTree(int n = 0){
tree = vector<seg>(4*n+1);
sz = n;
}
seg merge(seg a, seg b){
b.min+=a.sum;
if(b.min == a.min){
a.minct+=b.minct;
}
if(b.min < a.min){
a.min = b.min;
a.minct = b.minct;
}
a.sum+=b.sum;
return a;
}
void upd(int id, int l, int r){
if(l > q || r < q)
return;
if(l == q && r == q){
tree[id] = {val,val,1};
return;
}
int e = id*2+1, d = id*2+2, m = (l+r)>>1;
upd(e,l,m);
upd(d,m+1,r);
tree[id] = merge(tree[e],tree[d]);
}
void makeupd(int id, int x){
val = x;
q = id;
upd(0,0,sz-1);
}
} st;
vector<int> x;
vector<int> arr;
bool flag = 0;
void calc(int id, pii nmin, pii nmax){
resp-=isgood[id];
isgood[id] = (nmax.ff-nmin.ff+1)*(nmax.ss-nmin.ss+1) == id+1;
resp+=isgood[id];
mini[id] = nmin;
maxi[id] = nmax;
}
void comp(int id){
if(id == 1e9)
return;
int cur = x[id];
int dif = 1 - (int)(arr[cur-1] < id) - (int)(arr[cur+1] < id);
st.makeupd(id,dif);
}
void give_initial_chart(int H, int W, std::vector<int> R, std::vector<int> C) {
n = H*W;
if(H!=1){
flag = 0;
v = vector<pii>(n);
mini = vector<pii>(n);
maxi = vector<pii>(n);
isgood = vector<int>(n);
for(int i = 0; i < n; i++){
v[i] = {R[i], C[i]};
}
calc(0,v[0],v[0]);
for(int i = 1; i < n; i++){
pii nmin = mini[i-1], nmax = maxi[i-1];
nmin.ff = min(nmin.ff,v[i].ff);
nmin.ss = min(nmin.ss,v[i].ss);
nmax.ff = max(nmax.ff,v[i].ff);
nmax.ss = max(nmax.ss,v[i].ss);
calc(i,nmin,nmax);
}
return;
}
flag = 1;
st = SegTree(n);
x = vector<int>(n);
arr = vector<int>(n+2);
arr[0] = 1e9;
arr.back() = 1e9;
for(int i = 0; i < n; i++){
x[i] = C[i]+1;
arr[x[i]] = i;
}
for(int i = 0; i < n; i++){
comp(i);
}
}
int swap_seats(int a, int b) {
if(flag){
swap(x[a],x[b]);
swap(arr[x[a]],arr[x[b]]);
for(int i = -1; i <= 1; i++){
comp(arr[x[a]+i]);
comp(arr[x[b]+i]);
}
return st.tree[0].minct;
}
if(a > b)
swap(a,b);
swap(v[a],v[b]);
if(a == 0){
mini[a] = v[a];
maxi[a] = v[a];
a++;
}
for(int i = a; i <= b; i++){
pii nmin = mini[i-1], nmax = maxi[i-1];
nmin.ff = min(nmin.ff,v[i].ff);
nmin.ss = min(nmin.ss,v[i].ss);
nmax.ff = max(nmax.ff,v[i].ff);
nmax.ss = max(nmax.ss,v[i].ss);
calc(i,nmin,nmax);
}
return resp;
}
