Submission #1166691

#	Time	Username	Problem	Language	Result	Execution time	Memory
1166691		SG2Alok	Arranging Shoes (IOI19_shoes)	C++20	50 / 100	29 ms	16200 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#define ll long long
using namespace std;

vector<ll> pos[100005][2];
ll st[400005], lazy[400005];

void build(ll l, ll r, ll pos){
	if(l == r){
		st[pos] = l;
		return;
	}
	
	ll mid = (l + r) / 2;
	build(l, mid, pos * 2);
	build(mid + 1, r, pos * 2 + 1);
	
	st[pos] = max(st[pos * 2], st[pos * 2 + 1]);
}

void prop(ll pos){
	st[pos * 2] += lazy[pos];
	lazy[pos * 2] += lazy[pos];
	st[pos * 2 + 1] += lazy[pos];
	lazy[pos * 2 + 1] += lazy[pos];
	lazy[pos] = 0;
}

void update(ll l, ll r, ll L, ll R, ll pos, ll val){
	if(l > R || r < L) return;
	if(L <= l && r <= R){
		st[pos] += val;
		lazy[pos] += val;
		return;
	}
	
	prop(pos);
	
	ll mid = (l + r) / 2;
	update(l, mid, L, R, pos * 2, val);
	update(mid + 1, r, L, R, pos * 2 + 1, val);
	st[pos] = max(st[pos * 2], st[pos * 2 + 1]);
}

void update2(ll l, ll r, ll idx, ll pos, ll val){
	if(l == r){
		st[pos] = val;
		return;
	}
	
	prop(pos);
	
	ll mid = (l + r) / 2;
	if(idx <= mid) update2(l, mid, idx, pos * 2, val);
	else update2(mid + 1, r, idx, pos * 2 + 1, val);
	st[pos] = max(st[pos * 2], st[pos * 2 + 1]);
}

ll query(ll l, ll r, ll L, ll R, ll pos){
	if(l > R || r < L) return 0;
	if(L <= l && r <= R) return st[pos];
	
	prop(pos);
	
	ll mid = (l + r) / 2;
	return max(query(l, mid, L, R, pos * 2), query(mid + 1, r, L, R, pos * 2 + 1));
}

long long count_swaps(std::vector<int> s) {
	for(int i = s.size() - 1; i >= 0; i--){
		pos[abs(s[i])][s[i] > 0].push_back(i + 1);
	}
	
	build(1, s.size(), 1);
	
	ll ans = 0;
	vector<bool> udah(s.size() + 2);
	for(int i = 0; i < s.size(); i++){
		if(udah[i]) continue;
		
		ll nxt = pos[abs(s[i])][s[i] < 0].back();
		ans += query(1, s.size(), nxt, nxt, 1) - query(1, s.size(), i + 1, i + 1, 1) - 1 + (s[i] > 0);
		update(1, s.size(), i + 2, nxt - 1, 1, 1);
		update2(1, s.size(), nxt, 1, i + 2);
		pos[abs(s[i])][0].pop_back();
		pos[abs(s[i])][1].pop_back();
		udah[i] = true;
		udah[nxt - 1] = true;
	}
	
	return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 15
• Subtask 5: 20 / 20
• Subtask 6: 0 / 15