Submission #211828

#	Time	Username	Problem	Language	Result	Execution time	Memory
211828		MarcoMeijer	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	476 ms	148088 KiB

shoes

#include <bits/stdc++.h>
using namespace std;

//macros
typedef long long ll;
typedef pair<int, int> ii;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define INF 1e9
#define pb push_back
#define fi first
#define se second
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int MX = 2e5;
int n;
map<int, queue<int>> first;
int remPos[MX];

void addRemPos(int i, int x) {
	for(i++; i<=n; i+=i&-i) remPos[i] += x;
}
int getRemPos(int i) {
	int ans=0;
	for(i++; i>0; i-=i&-i) ans += remPos[i];
	return ans;
}
void addRemPos(int i, int j, int x) {
	addRemPos(j+1,-x);
	addRemPos(i,x);
}

ll count_swaps(vi S) {
	n = S.size();
	ll ans=0;
	RE(i,n+1) remPos[i] = 0;
	RE(i,n) {
		if(first[-S[i]].size()) {
			int pos = first[-S[i]].front(); first[-S[i]].pop();
			ans += i-pos-getRemPos(pos)-1;
			if(S[i] < 0) ans++;
			addRemPos(pos,i,1);
		} else {
			first[S[i]].push(i);
		}
	}
	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