Submission #393879

#	Time	Username	Problem	Language	Result	Execution time	Memory
393879		teehandsome	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	570 ms	148028 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define endl '\n'
#define INF 1e9+7
#define all(x) x.begin(),x.end()
using namespace std;
using namespace __gnu_pbds;
using ll=long long;
using pii=pair<int,int>;
using ppi=pair<int,pii>;
using oset=tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update>;

template<typename T>
void _print(vector<T> x) {cerr<<"{"; for(auto e:x) cerr<<e<<","; cerr<<"}";}
void _print(pii x) {cerr<<"{"<<x.first<<","<<x.second<<"}";}
template<typename T>
void _print(T x) {cerr<<x;}

void dbg() {cerr<<endl;}
template<typename Head,typename... Tail>
void dbg(Head H,Tail... T) {
    _print(H);
    if(sizeof...(T)) cerr<<",";
    else cerr<<"\"]";
    dbg(T...);
}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:[\"",dbg(__VA_ARGS__)

//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int mxn=2e5+10;
map<int,queue<int>> q;
int t[mxn];

void add(int pos,int val) {
    while(pos<mxn) {
        t[pos]+=val;
        pos+=pos&-pos;
    }
}
int get(int pos) {
    int res=0;
    while(pos>0) {
        res+=t[pos];
        pos-=pos&-pos;
    }
    return res;
}

long long count_swaps(std::vector<int> s) {
	int n=s.size();
	vector<bool> flag(n+1);
	for(int i=1;i<=n;i++) {
        q[s[i-1]].push(i);
	}
	ll ans=0;
	for(int i=1;i<=n;i++) {
        if(flag[i]) continue;
        assert(q[s[i-1]].front()==i);

        int p=q[-s[i-1]].front();
        q[s[i-1]].pop();
        q[-s[i-1]].pop();
        ans+=abs(p-i)-(get(p)-get(i-1));
        if(s[i-1]<0) ans--;
        add(i,1); add(p,1);
        flag[i]=true; flag[p]=true;
	}
	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