Submission #944795

#	Time	Username	Problem	Language	Result	Execution time	Memory
944795		PenguinsAreCute	Arranging Shoes (IOI19_shoes)	C++17	10 / 100	1088 ms	4308 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);}
	~ft() {v.clear();}
	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) {
		ll 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;
	ll ans = 696969;
	vector<int> t; for(int i=0;i<2*n;i++) t.push_back(i);
	do {
		bool ok = 1;
		for(int i=0;i<2*n;i+=2) if((s[t[i]]+s[t[i+1]])||s[t[i]]>0) ok = 0;
		if(!ok) continue;
		ll cur = 0;
		ft fenwick(2*n);
		for(int i=2*n;i--;) {
			cur += fenwick.qry(t[i]);
			fenwick.up(t[i]+1,1);
		}
		ans = min(ans, cur);
	} while(next_permutation(t.begin(),t.end()));
	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