Problem Link : http://codeforces.com/gym/101484/problem/B
Solution Idea:
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To solve this problem we need line sweep technique and some data structure. At first convert each rectangle in two element with respect to it x coordinate which both x coordinate have same y coordinates. Now call first x point opening and 2nd x point closing of a rectangle. Now take a array of custom data type. and store every opening and closing of rectangles and the query points and sort the the array in the basis of x coordinate of each element and in case of a tie take closing element first then query point and then opening point.
Now run a loop on the x axis and update every range by 1 if we find a opening and by -1 if we find a closing and if we find a query point just query the value of that point.
Handle the boundary condition carefully.
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define pii pair <int,int>
#define pll pair <long long,long long>
#define sc scanf
#define pf printf
#define Pi 2*acos(0.0)
#define ms(a,b) memset(a, b, sizeof(a))
#define pb(a) push_back(a)
#define MP make_pair
#define db double
#define ll long long
#define EPS 10E-10
#define ff first
#define ss second
#define sqr(x) (x)*(x)
#define D(x) cerr<<#x " = "<<(x)<<endl
#define VI vector <int>
#define DBG pf("Hi\n")
#define MOD 1000000007
#define CIN ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define SZ(a) (int)a.size()
#define sf(a) scanf("%d",&a)
#define sfl(a) scanf("%lld",&a)
#define sff(a,b) scanf("%d %d",&a,&b)
#define sffl(a,b) scanf("%lld %lld",&a,&b)
#define sfff(a,b,c) scanf("%d %d %d",&a,&b,&c)
#define sfffl(a,b,c) scanf("%lld %lld %lld",&a,&b,&c)
#define stlloop(v) for(__typeof(v.begin()) it=v.begin();it!=v.end();it++)
#define loop(i,n) for(int i=0;i<n;i++)
#define loop1(i,n) for(int i=1;i<=n;i++)
#define REP(i,a,b) for(int i=a;i<b;i++)
#define RREP(i,a,b) for(int i=a;i>=b;i--)
#define TEST_CASE(t) for(int z=1;z<=t;z++)
#define PRINT_CASE printf("Case %d: ",z)
#define LINE_PRINT_CASE printf("Case %d:\n",z)
#define CASE_PRINT cout<<"Case "<<z<<": "
#define all(a) a.begin(),a.end()
#define intlim 2147483648
#define infinity (1<<28)
#define ull unsigned long long
#define gcd(a, b) __gcd(a, b)
#define lcm(a, b) ((a)*((b)/gcd(a,b)))
using namespace std;
//using namespace __gnu_pbds;
//typedef tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
/*----------------------Graph Moves----------------*/
//const int fx[]={+1,-1,+0,+0};
//const int fy[]={+0,+0,+1,-1};
//const int fx[]={+0,+0,+1,-1,-1,+1,-1,+1}; // Kings Move
//const int fy[]={-1,+1,+0,+0,+1,+1,-1,-1}; // Kings Move
//const int fx[]={-2, -2, -1, -1, 1, 1, 2, 2}; // Knights Move
//const int fy[]={-1, 1, -2, 2, -2, 2, -1, 1}; // Knights Move
/*------------------------------------------------*/
/*-----------------------Bitmask------------------*/
//int Set(int N,int pos){return N=N | (1<<pos);}
//int reset(int N,int pos){return N= N & ~(1<<pos);}
//bool check(int N,int pos){return (bool)(N & (1<<pos));}
/*------------------------------------------------*/
struct data
{
int type,x,st,ed,id;
};
vector<int>x,y;
vector<data>v;
bool cmp(data a, data b)
{
if(a.x<b.x) return true;
if(a.x==b.x)
return a.type<b.type;
return false;
}
#define mx 300005
int tree[mx];
void update(int idx, int val)
{
for(; idx<mx && idx; idx+=(idx&-idx))
tree[idx]+=val;
}
int query(int idx)
{
int ret=0;
for(; idx; idx-=(idx&-idx))
ret+=tree[idx];
return ret;
}
int ans[mx];
int main()
{
// freopen("in.txt","r",stdin);
// freopen("out.txt","w",stdout);
int n,m;
sff(n,m);
for(int i=0; i<n; i++)
{
int a,b;
sff(a,b);
data temp;
temp.type=2;
temp.x=a;
temp.ed=temp.st=b;
temp.id=i;
v.pb(temp);
x.pb(a);
y.pb(b);
}
for(int i=0; i<m; i++)
{
int a,b,c,d;
sff(a,b);
sff(c,d);
x.pb(a);
x.pb(c);
y.pb(b);
y.pb(d);
data temp;
temp.type=1;
temp.x=c;
temp.st=b;
temp.ed=d;
v.pb(temp);
data temp1;
temp1.type=3;
temp1.x=a;
temp1.st=b;
temp1.ed=d;
v.pb(temp1);
}
// sort(all(x));
sort(all(y));
sort(all(v),cmp);
for(int i=0; i<SZ(v); i++)
{
data temp=v[i];
if(temp.type==1)
{
int a=lower_bound(all(y),temp.st)-y.begin()+1;
int b=lower_bound(all(y),temp.ed)-y.begin()+1;
update(a+1,-1);
update(b,+1);
}
else if(temp.type==3)
{
int a=lower_bound(all(y),temp.st)-y.begin()+1;
int b=lower_bound(all(y),temp.ed)-y.begin()+1;
update(a+1,+1);
update(b,-1);
}
else
{
int a=lower_bound(all(y),temp.st)-y.begin()+1;
int xx=query(a);
// int yy=query(a-1); // Never do this while range update on BIT -_-
ans[temp.id]=xx;
}
}
for(int i=0; i<n; i++)
printf("%d\n",ans[i]);
return 0;
}
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