Problem Link : http://codeforces.com/gym/101484/problem/B
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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; }