Submission #799776

#	Time	Username	Problem	Language	Result	Execution time	Memory
799776		Haidara	Regions (IOI09_regions)	C++17	100 / 100	4251 ms	78772 KiB

regions

/** * * * * * * * * * * * * * * * **\
 *                                 *
 *     Author: Haidara Nassour     *
 *  Coded in: YYYY\MM\DD HH:MM:SS  *
 *         Language: C++22         *
 *                                 *
\** * * * * * * * * * * * * * * * **/
#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#define FAST ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
//#define int long long
#define itn int
#define endl '\n'
#define rep(i,x,n) for(int i=(x);i<(n);i++)
#define FOR(i,n) rep(i,0,n)
#define repf(i,x,n) for(int i=(x);(n);i++)
#define per(i,x,n) for(int i=(x);i>(n);i--)
#define ROF(i,x) for(int i=x;i>=0;i--)
#define v(i) vector< i >
#define p(i,j) pair< i , j >
#define pii pair<int,int>
#define m(i,j) map< i , j >
#define um(i,j) unordered_map< i , j >
#define max_heap(i) priority_queue< i >
#define min_heap(i) priority_queue< i , vector< i > ,greater< i > >
#define ff first
#define sinf(x) const int inf=x;
#define smaxn(x) const int maxn=x;
#define ss second
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define pp push_back
#define mini(x,y) x=min(x,y)
#define maxi(x,y) x=max(x,y)
#define debug(x) cout<<endl<<#x<<"="<<x<<endl;
#define point(x) complex< x >
#define X real()
#define mp make_pair
#define Y imag()
#define add(x,y) x=(x+(y%mod))%mod
using namespace std;
using namespace __gnu_pbds;
void SIO(string name="",string name2="",string later="",string later2="")
{
    if(later=="")
    {
        later=".in";
        later2=".out";
    }
    else
    {
        if(later2=="")
            later2=later;
    }
    if(name!="")
    {
        if(name2=="")
            freopen((name+later).c_str(),"r",stdin);
        else
        {
            freopen((name+later).c_str(),"r",stdin);
            freopen((name2+later2).c_str(),"w",stdout);
        }
    }
}
template <class T> using o_set = tree<T, null_type, less<T>,rb_tree_tag, tree_order_statistics_node_update>;
template <class T> using o_multiset = tree<T, null_type, less_equal<T>,rb_tree_tag, tree_order_statistics_node_update>;
///order_of_key = find index of element x ( returned val is integer )
///find_by_order = find value at index x ( returned val is pointer )
/// to swap s1 and s2 we make the following: s1.swap(s2)
template<class T> T chmin(T &a,T b)
{
    if(b<a)
        a=b;
    return a;
}
template<class T> T chmax(T &a,T b)
{
    if(a<b)
        a=b;
    return a;
}
template<class T> T mxmn(T &a,T &b)
{
    int mx=max(a,b);
    int mn=min(a,b);
    a=mx,b=mn;
    return mx+mn;
}
const double pi=2.0*acos(0.0);
const double memory=1048576.0;
const int inf=1LL<<50LL;
const int mod=1e9+7;
const int maxn=200002;
int n,R,cnt[25005],r[maxn];
int in[maxn],out[maxn];
int tim=1;
v(int)graph[maxn],em[25005],emofr[25005],id(25005,0);
void dfs(int st=1,int par=-1)
{
    in[st]=tim++;
    emofr[r[st]].pp(in[st]);
    em[r[st]].pp(st);
    for(auto i:graph[st])
    {
        if(i==par)
            continue;
        dfs(i,st);
    }
    out[st]=tim++;
}
int ans[600][25005];
void go(int col,int st=1,int cur=0,int par=-1)
{
    if(r[st]==col)
        cur++;
    else
        ans[id[col]][r[st]]+=cur;
    for(auto i:graph[st])
    {
        if(i==par)
            continue;
        go(col,i,cur,st);
    }
}
signed main()
{
    int q;
    cin>>n>>R>>q;
    cin>>r[1];
    cnt[r[1]]++;
    rep(i,2,n+1)
    {
        int j;
        cin>>j>>r[i];
        cnt[r[i]]++;
        graph[j].pp(i);
    }
    dfs();
    int cur_id=0;
    rep(i,1,R+1)
    if(cnt[i]>200)
        id[i]=cur_id++,go(i);
    while(q--)
    {
        int r1,r2;
        cin>>r1>>r2;
        if(cnt[r1]>200)
            cout<<ans[id[r1]][r2]<<endl;
        else
        {
            int res=0;
            const auto &v=emofr[r2];
            for(auto i:em[r1])
            {
                res+=lower_bound(all(v),out[i])-upper_bound(all(v),in[i]);
            }
            cout<<res<<endl;
        }
        cout<<flush;
    }
}
/**
5 2
10
1
1 1
1 2
1 2
2 2
1 1

**/

Compilation message (stderr)

regions.cpp:93:18: warning: overflow in conversion from 'long long int' to 'int' changes value from '1125899906842624' to '0' [-Woverflow]
   93 | const int inf=1LL<<50LL;
      |               ~~~^~~~~~
regions.cpp: In function 'void SIO(std::string, std::string, std::string, std::string)':
regions.cpp:59:20: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   59 |             freopen((name+later).c_str(),"r",stdin);
      |             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
regions.cpp:62:20: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |             freopen((name+later).c_str(),"r",stdin);
      |             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
regions.cpp:63:20: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |             freopen((name2+later2).c_str(),"w",stdout);
      |             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 85 / 85