Submission #155773

#	Time	Username	Problem	Language	Result	Execution time	Memory
155773		Sasuke0004	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	652 ms	74360 KiB

shoes

#include <bits/stdc++.h>
#define ll long long 
using namespace std;
ll i,j,n,t,ans,k,b[2000001],fix[2000001],c[2000001],seg[2000001];
pair <ll,ll> a[2000001];
map <ll,ll> m;
vector <ll> v[2000001];
 void upd(ll h,ll l,ll r,ll val,ll ind) {
    if (ind<l || ind>r) return;
    if (l==ind && r==ind) {seg[h]=1;return;}
    upd(h*2,l,(l+r)/2,val,ind);
    upd(h*2+1,(l+r)/2+1,r,val,ind);
    seg[h]=seg[h*2]+seg[h*2+1];
}
ll get(ll h,ll l,ll r,ll L,ll R) {
    if (l>R || r<L) return 0;
    if (l>=L && r<=R) return seg[h];
    return get(h*2,l,(l+r)/2,L,R)+get(h*2+1,(l+r)/2+1,r,L,R);
}
int64_t count_swaps(vector<int> p){
    n=p.size()/2;
    for (i=1;i<=2*n;i++) {
        b[i]=p[i-1];
        c[i]=b[i];
        if (b[i]>0) {fix[b[i]]++;v[b[i]].push_back(i);}
    }
   for (i=1;i<=2*n;i++) {
        m[b[i]]=0;
       if (b[i]<0) {v[abs(b[i])].push_back(i);}
    }
    for (i=1;i<=2*n;i++) {
        if (b[i]>0)  m[b[i]]=0;
        else
        m[b[i]]+=1;
    }
    t=1;
    for (i=1;i<=2*n;i++) {
        if (b[i]==0) continue;
        if (b[i]>0) {
            a[t].first=v[b[i]][m[-1*b[i]]];
            a[t].second=i;
            m[-1*b[i]]++;
            m[b[i]]++;
            b[a[t].first]=0;
            b[a[t].second]=0;
            t++;
        }
        else
        {
            a[t].first=i;
            a[t].second=v[-1*b[i]][m[-1*b[i]]];
            m[-1*b[i]]++;
            m[b[i]]++;
            b[a[t].first]=0;
            b[a[t].second]=0;
            t++;
        }
    } 
       for (i=1;i<=n;i++) {
        if (c[min(a[i].first,a[i].second)]>0) {ans=ans+max(a[i].first,a[i].second)-min(a[i].first,a[i].second);}
        else
        ans=ans+max(a[i].second,a[i].first)-min(a[i].second,a[i].first)-1;
    }
    for (i=1;i<=n;i++) {
        ans=ans-get(1,1,2*n+1,min(a[i].first,a[i].second),max(a[i].first,a[i].second));
        upd(1,1,2*n+1,1,a[i].first);
        upd(1,1,2*n+1,1,a[i].second);
    } 
    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