//by szh
#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pii pair<int,int>
#define pll pair<long long,long long>
#define pb push_back
#define debug(x) cerr<<#x<<"="<<x<<endl
#define pq priority_queue
#define inf 0x3f
#define rep(i,a,b) for (int i=a;i<(b);i++)
#define MP make_pair
#define SZ(x) (int(x.size()))
#define ll long long
#define mod 1000000007
#define ALL(x) x.begin(),x.end()
void inc(int &a,int b) {a=(a+b)%mod;}
void dec(int &a,int b) {a=(a-b+mod)%mod;}
int lowbit(int x) {return x&(-x);}
ll p0w(ll base,ll p) {ll ret=1;while(p>0){if (p%2ll==1ll) ret=ret*base%mod;base=base*base%mod;p/=2ll;}return ret;}
#include "seats.h"
const int maxn = 1e6+10;
pii pos[maxn];
int n;
int ret = 1;
int ans[maxn];
int minx[maxn],maxx[maxn],miny[maxn],maxy[maxn];
void give_initial_chart(int H, int W, std::vector<int> R, std::vector<int> C) {
rep(i,0,H*W) pos[i] = {R[i],C[i]};
n = H*W;
minx[0] = maxx[0] = pos[0].fi;
miny[0] = maxy[0] = pos[0].se;
ans[0] = 1;
rep(i,1,n) {
minx[i] = min(minx[i-1],pos[i].fi);
maxx[i] = max(maxx[i-1],pos[i].fi);
miny[i] = min(miny[i-1],pos[i].se);
maxy[i] = max(maxy[i-1],pos[i].se);
if ((maxx[i]-minx[i]+1) * (maxy[i]-miny[i]+1) == i+1) ans[i] = 1,ret++;
}
}
int swap_seats(int a, int b) {
if (a>b) swap(a,b);
swap(pos[a],pos[b]);
rep(i,a,b+1) {
ret -= ans[i];
if (i==0) minx[i] = maxx[i] = pos[i].fi, miny[i] = maxy[i] = pos[i].se;
else {
minx[i] = min(minx[i-1],pos[i].fi);
maxx[i] = max(maxx[i-1],pos[i].fi);
miny[i] = min(miny[i-1],pos[i].se);
maxy[i] = max(maxy[i-1],pos[i].se);
}
if ((maxx[i]-minx[i]+1) * (maxy[i]-miny[i]+1) == i+1) ret++,ans[i]=1;
else ans[i] = 0;
}
return ret;
}
