Submission #609370

#	Time	Username	Problem	Language	Result	Execution time	Memory
609370		nyaruhodo	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	151 ms	15660 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

// segtree or pbds ig
vector<ll> seg;

void psh(ll v){
	seg[v*2] += seg[v];
	seg[v*2+1] += seg[v];
	seg[v]=0;
}

void update(ll v,ll l,ll r,ll tl,ll tr){
	if(l > r) return;
	if(tl==l && tr == r) {
		seg[v]++;
		return;
	}

	ll tm=(tl+tr)/2;
	update(v*2,l,min(r,tm),tl,tm);
	update(v*2+1,max(l,tm+1),r,tm+1,tr);	
}

ll query(ll v,ll tl,ll tr,ll s){
	if(tl==tr && tl==s) return seg[v];
	psh(v);
	ll tm=(tl+tr)/2;
	if(s <= tm)	return query(v*2,tl,tm,s);
	else return query(v*2+1,tm+1,tr,s);
}



long long count_swaps(std::vector<int> s) {
	set<pair<ll,ll>> st; // val, pos
	ll cnt=0,n=s.size();
	seg.resize(4*(n+10),0);

	for(ll i = 0;i < s.size();i++){
		auto lb = st.lower_bound({-s[i],-1});
		if(lb == st.end() || lb->first!=-s[i]){
			st.insert({s[i],i});
			continue;
		}

		auto p = *lb;
		st.erase(lb);
		ll add = query(1,1,n,p.second+1);
		cnt+=i-(p.second+add)-1;
		update(1,p.second+1,i+1,1,n);
		if(s[i]<0) cnt++;
	}

	return cnt;
}

/*


*/

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:43:17: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |  for(ll i = 0;i < s.size();i++){
      |               ~~^~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 15 / 15