#include"seats.h"
#include<iostream>
#include<algorithm>
using namespace std;
int w,h;
vector<int>x,y;
vector<vector<int>>mat;
int arr[1000000];
int get_mat(int x,int y){
if(x<0||x>=w||y<0||y>=h)
return w*h;
return mat[x][y];
}
void upd_sq(int x,int y,int mul){ // 1 for adding and -1 for removing
vector<int>vals={get_mat(x,y),get_mat(x+1,y),get_mat(x,y+1),get_mat(x+1,y+1)};
sort(vals.begin(),vals.end());
/*for(int i:vals)
cout<<i<<" ";
cout<<endl;*/
for(int i=vals[0];i<vals[1];i++)
arr[i]+=mul;
for(int i=vals[2];i<vals[3];i++)
arr[i]+=mul;
}
void give_initial_chart(int H,int W,vector<int>R,vector<int>C){
x=C;
y=R;
h=H;
w=W;
mat=vector<vector<int>>(w,vector<int>(h));
for(int i=0;i<w*h;i++)
mat[x[i]][y[i]]=i;
for(int x=-1;x<w;x++)
for(int y=-1;y<h;y++)
upd_sq(x,y,1);
}
int swap_seats(int a,int b){
upd_sq(x[a]-1,y[a]-1,-1);
upd_sq(x[a]-1,y[a],-1);
upd_sq(x[a],y[a]-1,-1);
upd_sq(x[a],y[a],-1);
upd_sq(x[b]-1,y[b]-1,-1);
upd_sq(x[b]-1,y[b],-1);
upd_sq(x[b],y[b]-1,-1);
upd_sq(x[b],y[b],-1);
swap(mat[x[a]][y[a]],mat[x[b]][y[b]]);
swap(x[a],x[b]);
swap(y[a],y[b]);
upd_sq(x[a]-1,y[a]-1,1);
upd_sq(x[a]-1,y[a],1);
upd_sq(x[a],y[a]-1,1);
upd_sq(x[a],y[a],1);
upd_sq(x[b]-1,y[b]-1,1);
upd_sq(x[b]-1,y[b],1);
upd_sq(x[b],y[b]-1,1);
upd_sq(x[b],y[b],1);
int res=0;
for(int i=0;i<w*h;i++)
if(arr[i]==4)
res++;
return res;
}
