Submission #398615

#	Time	Username	Problem	Language	Result	Execution time	Memory
398615		richyrich	Arranging Shoes (IOI19_shoes)	C++17	10 / 100	14 ms	19092 KiB

shoes

#include <bits/stdc++.h>
using namespace std;
#define ll long long
const ll MOD = 1e9+7;
const ll N = 2e5+10;
const ll inf = 1e9+100;
const double eps = 1;
ll n, a[N], t[N*4];
set<ll> L[N], R[N];
ll ans;
bool used[N];
void update(ll tv, ll tl, ll tr, ll l, ll r) {
	if(l > r) return;
	if(tl == l && tr == r) {
		t[tv]++;
		return;
	}
	else {
		ll tm =(tl + tr) >> 1;
		update(tv * 2, tl, tm, l, min(tm, r));
		update(tv * 2 + 1, tm + 1, tr, max(tm + 1, l), r);
	}
} 
ll get(ll tv, ll tl, ll tr, ll pos) {
	ll tm = (tl+tr)>>1;
	if(tl == tr && tl == pos) return t[tv];
	else {
		if(pos <= tm) return t[tv] + get(tv * 2, tl, tm, pos);
		else return t[tv] + get(tv * 2 +1, tm + 1, tr, pos);
	}
}
long long count_swaps(std::vector<int> s) {
	/*for(ll c : s) prllf("%d ", c);
	prllf("\n");*/
	ans = 0;
    n = s.size();
    for(ll i = 1;i <= n;i++) {
    	a[i] = s[i-1];
    	if(a[i] < 0) L[-a[i]].insert(i);
    	else R[a[i]].insert(i);
    }
    /*for(ll i = 1; i <= 2; i++) {
    	prllf("left %d:", i);
    	for(ll c : L[i]) prllf("%d ", c);
    	prllf("\n");
    }
    for(ll i = 1; i <= 2; i++) {
    	prllf("right %d:", i);
    	for(ll c : R[i]) prllf("%d ", c);
    	prllf("\n");
    }*/
    for(ll i = 1; i <= n; i++){
    	if(used[i]) continue;
    	ll pos;
    	if(a[i] < 0) {
    		pos = *R[-a[i]].begin();
    		L[-a[i]].erase(i);
    		R[-a[i]].erase(pos);
    		ans += pos-(i+1) + get(1, 1, n, pos) - get(1, 1, n, i+1);
    		used[pos] = used[i] = 1;
    	}
    	else {
    		pos = *L[a[i]].begin();
    		R[a[i]].erase(i);
    		L[a[i]].erase(pos);
    		ans += pos - i + get(1, 1, n, pos) - get(1, 1, n, i);
    		used[pos] = used[i] = 1;
    	}
    	if(i+1 <= pos - 1)update(1, 1, n, i+1, pos - 1);
    }
    return ans;
}

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