제출 #1250435

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1250435		Edu175	3개의 봉우리 (IOI25_triples)	C++20	24.47 / 100	572 ms	22340 KiB

triples

#include "triples.h"
#include <bits/stdc++.h>
#define pb push_back
#define fst first
#define snd second
#define fore(i,a,b) for(ll i=a,ioi=b;i<ioi;i++)
#define SZ(x) ((ll)x.size())
#define ALL(x) x.begin(),x.end()
#define mset(a,v) memset((a),(v),sizeof(a))
#define imp(v) {for(auto i:v)cout<<i<<" ";cout<<"\n";}
using namespace std;
typedef long long ll;
typedef pair<ll,ll> ii;
typedef vector<ll> vv;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,popcnt,lzcnt")
const ll MAXN=2e5;

const ll C=500;

long long count_triples(vector<int> __h) {
	ll n=SZ(__h);
	vv h;
	fore(i,0,n)h.pb(__h[i]);
	
	ll fg=1;
	fore(i,0,n-1)fg&=h[i]<=h[i+1];
	
	set<vv> all;
	
	auto israre=[&](ll i, ll j, ll k){
		return h[i]==abs(j-k)&&h[j]==abs(i-k)&&h[k]==abs(i-j);
	};
	
	auto good=[&](vv s){
		assert(SZ(s)==3);
		vector<ll> ds,hs;
		fore(i,0,3)fore(j,i+1,3)ds.pb(abs(s[i]-s[j]));
		fore(i,0,3)hs.pb(h[s[i]]);
		sort(ALL(hs));
		sort(ALL(ds));
		return ds==hs;
	};
	
	auto eval=[&](ll i, ll j, ll k, bool allow=0){
		vv s={i,j,k}; sort(ALL(s));
		if(s[0]==s[1]||s[1]==s[2])return;
		if(s[0]<0||s[2]>=n)return;
		if(good(s)&&(allow||!israre(i,j,k)))all.insert(s);
	};
	
	auto doit=[&](ll i, ll j){
		if(j<0||j>=n)return;
		vv ind={i,j};
		fore(wd,0,2)fore(wf,0,2)fore(ws,0,2){
			ll d=h[ind[wd]];
			ll f=ind[wf];
			ll s=ws?1:-1;
			ll k=f+s*d;
			eval(i,j,k);
		}
	};
	
	fore(i,0,n)doit(i,i+h[i]),doit(i,i-h[i]);
	if(fg)return SZ(all);
	
	// faltan las otras, las rare
	
	ll res=0;
	if(*max_element(ALL(h))<50){
		fore(i,0,n){
			ll b=h[i];
			fore(j,max(0ll,i-b+1),i){
				eval(j,i,j+b,1);
			}
		}
	}
	else {
		
		map<ll,vv> h0,h1;
		
		map<ll,bitset<MAXN>>mp1;
		fore(i,0,n){
			h0[h[i]-i].pb(i);
			h1[h[i]+i].pb(i);
		}
		for(auto [key,vec]:h1){
			if(SZ(vec)>=C){
				for(auto i:vec)mp1[key][i]=1;
			}
		}
		for(auto [asd,vec]:h0){
			bitset<MAXN>b0;
			for(auto i:vec)b0[h[i]]=1;
			ll pr=0;
			reverse(ALL(vec));
			for(auto i:vec){
				ll v=h[i];
				ll d=n-v; d-=pr;
				assert(d>0);
				b0<<=d; pr+=d;
				bitset<MAXN> b1;
				if(mp1.count(v+i))b1=mp1[v+i];
				else for(auto i:h1[v+i])b1[i]=1;
				ll c=(b0&b1).count();
				res+=c;
			}
		}
	}
	// for(auto v:all){
	// 	for(auto i:v)cout<<i<<" ";;cout<<": ";
	// 	for(auto i:v)cout<<h[i]<<" ";;cout<<"\n";
	// }
	return SZ(all)+res;
}

vector<int> construct_range(int M, int K) {
	ll n=M;
	vector<int> a={1,2,1};
    ll u=2;
    while(SZ(a)<n){
        ll v=SZ(a)+1;
        fore(i,0,u+1)a.pb(v-i);
        u=v;
    }
    while(SZ(a)>n||a.back()>=n)a.pop_back();
    return a;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 6 / 6
• Subtask 3: 0 / 10
• Subtask 4: 11 / 11
• Subtask 5: 0 / 16
• Subtask 6: 0 / 19
• Subtask 7: 4 / 5
• Subtask 8: 1.8425 / 5
• Subtask 9: 0.7729 / 5
• Subtask 10: 0.3424 / 5
• Subtask 11: 0.3751 / 5
• Subtask 12: 0.1342 / 5