Submission #486903

#	Time	Username	Problem	Language	Result	Execution time	Memory
486903		Haidara	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	203 ms	109860 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);
    }
    set <int> s[maxn*2];
    ll count_swaps(v(int)a)
    {
        n=a.size();
        build();
        FOR(i,n)
            s[a[i]+n].insert(i+1);
        ll ans=0;
        v(bool)vis(maxn*2,0);
        FOR(i,n){
            if(vis[i+1])
            	continue;
            ll poz=*s[-a[i]+n].begin();
            s[a[i]+n].erase(i+1);
            s[-a[i]+n].erase(poz);
            ans+=query(i-1,poz-1)-2;
            if(a[i]>0)
                ans++;
            update(i);
            update(poz-1);
            vis[i+1]=vis[poz]=1;
        }
        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