Submission #486900

#	Time	Username	Problem	Language	Result	Execution time	Memory
486900		Haidara	Arranging Shoes (IOI19_shoes)	C++17	0 / 100	29 ms	47308 KiB

shoes

#include<bits/stdc++.h>
    #include<shoes.h>
    #define rep(i,x,n) for(int i=(x);i<(n);i++)
    #define FOR(i,n) rep(i,0,n)
    #define v(i) vector< i >
    #define ll long long
    #define pp push_back 
    using namespace std;
    const ll inf=1LL<<62LL;
    const ll mod=1e9+7;
    const ll maxn=1000200;
    ll st[4*maxn];
    int n;
    ll query(int ql,int qr,int l=0,int r=n-1,int inx=1)
    {
    	if(ql<=l&&r<=qr)
    		return st[inx];
    	if(ql>r||l>qr)
    		return 0;
    	int mid=l+(r-l)/2;
    	return query(ql,qr,mid+1,r,inx*2+1)+query(ql,qr,l,mid,inx*2);
    }
    void update(int pos,int l=0,int r=n-1,int inx=1)
    {
    	if(l==r)
    	{
    		st[inx]=0;
    		return ;
    	}
    	int mid=l+(r-l)/2;
    	if(pos<=mid)
    		update(pos,l,mid,inx*2);
    	else 
    		update(pos,mid+1,r,inx*2+1);
    	st[inx]=st[inx*2]+st[inx*2+1];
    }
    int build(int l=0,int r=n-1,int inx=1)
    {
    	if(l==r)
    		return st[inx]=1;
    	int mid=l+(r-l)/2;
    	return st[inx]=build(l,mid,inx*2)+build(mid+1,r,inx*2+1);
    }
    ll count_swaps(v(int)a)
    {
    	ll ans=0;
    	n=a.size();
    	build();
    	v(int)l[maxn],r[maxn];
    	for(int i=n-1;i>=0;i--)
    	if(a[i]<0)
    		l[-a[i]].pp(i);
    	else 
    		r[a[i]].pp(i);
    	v(bool)vis(maxn,0);
    	FOR(i,n)
    	{
    		if(vis[i])
    			continue;
    		if(a[i]>0)
    			ans++;
    		a[i]=abs(a[i]);
    		int left=l[a[i]].back();
    		l[a[i]].pop_back();
    		int right=r[a[i]].back();
    		r[a[i]].pop_back();
    		if(left>right)
    			swap(left,right);
    		ans+=(query(left,right)-2);
          update(left);
    		update(right);
    	}
    	return ans;
    }

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