제출 #1152867

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1152867		KluydQ	Split the sequence (APIO14_sequence)	C++20	100 / 100	1471 ms	88652 KiB

sequence

#include <bits/stdc++.h>
//#include "grader.h"
 
#define respagold ios_base::sync_with_stdio(0), cin.tie(0);
//#define int long long
#define ll long long
#define int2 __int128_t
#define FOR( i, x, n, d ) for( int i = x; i <= n; i += d )
#define FORR( i, x, n, d ) for( int i = x; i >= n; i -= d )
#define F first
#define S second
#define all(x) x.begin(), x.end()
#define sz(x) (int)(x.size())
#define pb push_back
#define ins insert
#define lb lower_bound
#define ub upper_bound
#define pii pair <int, int>
#define mkp make_pair
 
using namespace std;
 
const int N = 1e5 + 123;
const ll inf = 1e18;
 
ll a[N], b[N], n, m, k, z, w, x, y, mm[N], cc[N];
ll dp[N];
int par[N][201];

mt19937 rng( chrono::steady_clock::now().time_since_epoch().count());
 
int rand( int l, int r )
{
    uniform_int_distribution <int> uid( l, r );
    return uid( rng );
}
ll calc( int a, int b )
{
	if( mm[a] == mm[b] ) return inf;
	return ( cc[b] - cc[a] ) / ( mm[a] - mm[b] );
}
vector <ll> ve;
pair <ll, pair <ll, ll>> sv[N], sv1[N];

void add( int nw )
{
	int siz = sz(ve);
	while( siz > 1 && calc( ve[siz - 2], ve[siz - 1] ) > calc( ve[siz - 1], nw ) ) ve.pop_back(), siz --;
	ve.pb(nw);
}
pair <ll, ll> get( ll x )
{
	int l = 0, r = sz(ve) - 1, res = 0;
	
	while( l <= r )
	{
		int md = ( l + r ) >> 1;
		
		if(( md == 0 ? -inf : calc(ve[md], ve[md - 1]) ) < x ) l = md + 1, res = md;
		else r = md - 1;
	}
	return { mm[ve[res]] * x + cc[ve[res]], ve[res] };
}
void solve()
{
	cin >> n >> k;
	
	FOR( i, 1, n, 1 ) cin >> a[i], b[i] = b[i - 1] + a[i];
	
	mm[0] = cc[0] = 0;
	sv1[0].F = 0;
	
	FOR( bl, 1, k, 1 )
	{
		FOR( i, bl, n - k + bl - 1, 1 )
		{
			// for i find k that ( dp[k] + sum(k + 1, i) * sum(i + 1, n) ) is max
			
			// dp[i] = dp[k] + ( b[i] - b[k] ) * ( b[n] - b[i] )
			// dp[i] = dp[k] + b[i] * b[n] - b[i] * b[i] - b[k] * b[n] + b[k] * b[i];
			// dp[i] = ( dp[k] - b[k] * b[n] ) + ( b[i] * b[n] - b[i] * b[i] ) + ( b[k] * b[i] )
			
			add( sv1[i - 1].F );
			
			pair <ll, ll> j = get( b[i] );
			dp[i] = j.F + b[i] * b[n] - b[i] * b[i];
			sv[i] = { i, { b[i], dp[i] - b[i] * b[n] }};
			par[i][bl] = j.S;
		}
		ve.clear();
		FOR( i, 1, n, 1 ) sv1[i] = sv[i], mm[i] = sv[i].S.F, cc[i] = sv[i].S.S;
	}
	ll ans = -inf, id = 0;
	
	FOR( i, 1, n - 1, 1 )
	{
		if( dp[i] >= ans ) ans = dp[i], id = i;
	}
	vector <ll> v;
	FORR( blo, k, 1, 1 ) v.pb( id ), id = par[id][blo];
	reverse( all( v ));
	cout << ans << '\n';
	for( auto i : v ) cout << i << ' ';
}
signed main() 
{
//	freopen("connect.in", "r", stdin);
//	freopen("connect.out", "w", stdout);
	    
    respagold
    
    int test = 1;
    
    if( !test ) cin >> test;
	
	while( test -- )
	{
		solve();
	}
}
// solved by KluydQ

• Subtask 1: 11 / 11
• Subtask 2: 11 / 11
• Subtask 3: 11 / 11
• Subtask 4: 17 / 17
• Subtask 5: 21 / 21
• Subtask 6: 29 / 29