Submission #783479

#	Time	Username	Problem	Language	Result	Execution time	Memory
783479		bane	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	245 ms	276080 KiB

shoes

#include<bits/stdc++.h>
#include<queue>
#include "shoes.h"
using namespace std;
const int nax = (int)1e6+1;
int n;

struct Segtree{

	int t[nax * 3];
	
	void built(int l = 0, int r = n - 1, int k = 1){
		if (l == r){
			t[k] = 1;
			return;
		}
		int mid = (l+r)/2;
		built(l,mid,k*2);
		built(mid+1,r,k*2+1);
		t[k] = t[k * 2] + t[k * 2 + 1];
	}

	void trigger(int pos, int l = 0, int r = n - 1, int k = 1){
		if (l == r){
			t[k] = 0;
			return;
		}

		int mid = (l+r) / 2;
		if (pos <= mid) trigger(pos,l,mid,k*2);
		else  trigger(pos,mid+1,r,k*2+1);
		t[k] = t[k * 2] + t[k * 2 + 1];
	}

	int range_get(int a, int b, int l = 0, int r = n - 1, int k = 1){
		if (a > b)return 0;
		if (l >= a && r <= b)return t[k];
		if(l > b || r < a)return 0;
		int mid = (l+r)/2;
		return range_get(a,b,l,mid,k*2)+range_get(a,b,mid+1,r,k*2+1);
	}

} st;


long long count_swaps(std::vector<int> s) {
	n = (int)s.size();
	st.built();
	vector<int>used(n+1,0);
	queue<int>Left[n+1];
	queue<int>Right[n+1];
	for (int i = 0; i < n; i++){
		if (s[i] < 0){
			Left[-s[i]].push(i);
		}else{
			Right[s[i]].push(i);
		}
	}
	long long ans = 0;
	for (int i = 0; i < n; i++){
		if (used[i])continue;
		if (s[i] < 0){
			//left
			Left[-s[i]].pop();
			assert(Right[s[i]*(-1)].size()>0);
			int R = Right[-s[i]].front();
			Right[-s[i]].pop();
			st.trigger(R);
			used[i]=1;
			used[R]=1;
			ans += st.range_get(i+1,R);
			st.trigger(i);
		}else{
			//right
			Right[s[i]].pop();
			assert(Left[s[i]].size()>0);
			int L = Left[s[i]].front();
			Left[s[i]].pop();
			st.trigger(L);
			used[i]=1;
			used[L]=1;
			ans += st.range_get(i,L);
			//printf("query : %d\n", st.range_get(i,L));
			st.trigger(i);
		}
		//printf("%lld\n", ans);
		
	}
	return ans;
}

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