Submission #1070399

#	Time	Username	Problem	Language	Result	Execution time	Memory
1070399		thdh__	Untitled (POI11_rot)	C++17	63 / 100	31 ms	14172 KiB

Main

#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#define ll long long
#define pb push_back
#define eb emplace_back
#define pu push
#define ins insert
#define bruh ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define ff(x,a,b,c) for (auto x=a;x<=b;x+=c)
#define fd(x,a,b,c) for (auto x=a;x>=b;x-=c)
#define int ll

using namespace std;
//mt19937 mt(chrono::steady_clock::now().time_since_epoch().count());

typedef pair<int, int> ii;
const int N = 2e5+5;
const int mod = 1e9+7;
const int inf = 1e18;
using cd = complex<double>;
const long double PI = acos(-1);
int power(int a,int b) {ll x = 1;if (a >= mod) a%=mod; while (b) {if (b & 1) x = x*a % mod;a = a*a % mod;b>>=1;}return x;} 

int n, root, sz[N], l[N], r[N], idx = 0, ans, sum, bit[N];

//BIT
void update(int u,int val)
{
    for (;u<=n+5;u += u&(-u)) bit[u] += val;
}

int get(int u)
{
    int res = 0;
    for (;u>0;u -= u&(-u)) res += bit[u];
    return res;
}

void reset(int u)
{
    if (u<=n) 
    {
        update(u,-1); return;
    }
    reset(l[u]); reset(r[u]);
}

void push(int u)
{
    if (u<=n) 
    {
        update(u,1); return;
    }
    push(l[u]), push(r[u]);
}

void calc(int u)
{
    if (u<=n) 
    {
        sum += get(n)-get(u); return;
    }
    calc(l[u]); calc(r[u]);
}

void dfs(int u)
{
    if (u<=n) 
    {
        update(u,1); return;
    }
    dfs(r[u]);
    reset(r[u]);
    dfs(l[u]); sum = 0;
    calc(r[u]); push(r[u]);
    ans += min(sum, sz[l[u]]*sz[r[u]]-sum);
}

int init()
{
    int x; cin>>x;
    if (x) 
    {
        sz[x] = 1; return x;
    }
    idx++; int i = idx-1;
    l[i] = init();
    r[i] = init();
    sz[i] += sz[l[i]] + sz[r[i]];
    //cout<<i<<endl<<l[i]<<" "<<r[i]<<endl;
    if (sz[l[i]]<sz[r[i]]) swap(l[i],r[i]);
    return i;
}

void solve()
{
	cin>>n;
    idx = n+1;
    int root = init();
    dfs(root);
    cout<<ans;
}

signed main()
{
	bruh
	//freopen("input.inp","r",stdin);
	//freopen("output.inp","w",stdout);
	int t = 1;
	//cin>>t;
	while (t--)
	{
		solve();
		cout<<"\n";
	}
}

• Subtask 1: 9 / 9
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 9 / 9
• Subtask 5: 9 / 9
• Subtask 6: 9 / 9
• Subtask 7: 9 / 9
• Subtask 8: 0 / 9
• Subtask 9: 0 / 9
• Subtask 10: 0 / 9
• Subtask 11: 0 / 10