Submission #1249778

#	Time	Username	Problem	Language	Result	Execution time	Memory
1249778		Edu175	Triple Peaks (IOI25_triples)	C++20	42.47 / 100	2095 ms	22196 KiB

triples

#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;

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 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){
		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))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
	
	fore(i,0,n){
		ll b=h[i];
		fore(j,max(0ll,i-b+1),i){
			eval(j,i,j+b);
		}
	}
	
	return SZ(all);
}

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;
}
/*
int main(){
    ll n; cin>>n;
    // vector<int> a(n);
    //fore(i,0,n){
      //  cin>>a[i];
   // }
    
    auto a=construct_range(n,1);
    cout<<SZ(a)<<"\n";
    imp(a)
    cout<<count_triples(a)<<"\n";
}*/

• Subtask 0: 0 / 0
• Subtask 1: 8 / 8
• Subtask 2: 6 / 6
• Subtask 3: 10 / 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