Submission #944717

#	Time	Username	Problem	Language	Result	Execution time	Memory
944717		PenguinsAreCute	Arranging Shoes (IOI19_shoes)	C++17	10 / 100	30 ms	10044 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
struct ft {
	vector<int> v; int n;
	ft(int _n): n(_n) {v.resize(n+1,0);}
	inline int lsb(int x) {return x&(-x);}
	void up(int x, int u) {
		for(;x<=n;x+=lsb(x)) v[x]+=u;
	}
	int qry(int x) {
		int ans = 0;
		for(;x;x-=lsb(x)) ans += v[x];
		return ans;
	}
};
long long count_swaps(std::vector<int> s) {
	int n = s.size() / 2;
	vector<int> v, pos[n+1];
	for(int i=0;i<2*n;i++) {
		if(s[i]<0) {
			v.push_back(i);
			v.push_back(0);
		} else pos[s[i]].push_back(i);
	}
	for(int i=1;i<=n;i++) reverse(pos[i].begin(),pos[i].end());
	for(int i=0;i<2*n;i+=2) {
		v[i+1]=end(pos[-s[v[i]]])[-1];
		pos[-s[v[i]]].pop_back();
	}
	int ans = 0; ft fenwick(2*n);
	for(int i=2*n;i--;) {
		ans += fenwick.qry(v[i]);
		fenwick.up(v[i]+1,1);
	}
	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