Submission #211140

#	Time	Username	Problem	Language	Result	Execution time	Memory
211140		arctan	Arranging Shoes (IOI19_shoes)	C++14	50 / 100	350 ms	295844 KiB

shoes

#include<bits/stdc++.h>
#include "shoes.h"
using namespace std;
#define pb push_back
#define rep(i,n) for(ll i=0;i<n;i++)
#define rep1(i,n) for(ll i=1;i<=n;i++)
#define mp make_pair
#define F first
#define S second
#define pf pop_front
#define IOS ios_base::sync_with_stdio(0); cin.tie(0)
typedef long long ll;
const ll mod=1e9+7;
const ll maxn=200005;
const ll inf=1e9+7;
unordered_map<ll,queue<ll>> m;
ll bit[maxn];
inline ll lsb(int x)
{
    return x&(-x);
}
void add(int x,int v)
{
    int cnt=0;
  	while(x<maxn)
    {
        bit[x]+=v;
        x+=lsb(x);
      	cnt++;
      	assert(cnt<=30);
    }
}
ll query(ll x)
{
    ll res=0;
  	int cnt=0;
    while(x)
    {
        res+=bit[x];
        x-=lsb(x);
      	cnt++;
      	//assert(cnt<=10);
    }
    return res;
}
ll count_swaps(std::vector<int> s)
{
    rep(i,s.size())
    {
        m[s[i]].push(i);
        add(i+1,1);
    }
    ll sum=0;
    rep(i,s.size())
    {
        queue<ll> q=m[-s[i]];
        if(q.empty()) continue;
        if(m[s[i]].front()!=i) continue;
        ll p=q.front();
        m[-s[i]].pop();
        m[s[i]].pop();
        sum+=query(p)-query(i+1);
        if(s[i]>0) sum++;
        //cout<<i<<" "<<sum<<"\n";
        add(p+1,-1);
        add(i+1,-1);
        if(i>10000) assert(0);
    }



    return sum;
}

Compilation message (stderr)

shoes.cpp: In function 'll count_swaps(std::vector<int>)':
shoes.cpp:5:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define rep(i,n) for(ll i=0;i<n;i++)
shoes.cpp:48:9:
     rep(i,s.size())
         ~~~~~~~~~~            
shoes.cpp:48:5: note: in expansion of macro 'rep'
     rep(i,s.size())
     ^~~
shoes.cpp:5:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define rep(i,n) for(ll i=0;i<n;i++)
shoes.cpp:54:9:
     rep(i,s.size())
         ~~~~~~~~~~            
shoes.cpp:54:5: note: in expansion of macro 'rep'
     rep(i,s.size())
     ^~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 15
• Subtask 5: 20 / 20
• Subtask 6: 0 / 15