oj.uz

Submission #90039

# Submission time Handle Problem Language Result Execution time Memory
90039 2018-12-19T22:01:16 Z qkxwsm Chase (CEOI17_chase) C++14
100 / 100
 2932 ms 218216 KB 
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/rope>

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;

random_device(rd);
mt19937 rng(rd());
const long long FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();

struct custom_hash
{
	template<class T>
	unsigned long long operator()(T v) const
	{
		unsigned long long x = v;
		x += FIXED_RANDOM; x += 11400714819323198485ull;
		x = (x ^ (x >> 30)) * 13787848793156543929ull;
		x = (x ^ (x >> 27)) * 10723151780598845931ull;
		return x ^ (x >> 31);
	}
};

template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T, class U> using hash_table = gp_hash_table<T, U, custom_hash>;

template<class T>
void readi(T &x)
{
	x = 0;
	bool negative = false;
	char c = ' ';
	while (c < '-')
	{
		c = getchar();
	}
	if (c == '-')
	{
		negative = true;
		c = getchar();
	}
	while (c >= '0')
	{
		x = x * 10 + (c - '0');
		c = getchar();
	}
	if (negative)
	{
		x = -x;
	}
}
template<class T>
void printi(T output)
{
	if (output == 0)
	{
		putchar('0');
		return;
	}
	if (output < 0)
	{
		putchar('-');
		output = -output;
	}
	int buf[20], n = 0;
	while(output)
	{
		buf[n] = ((output % 10));
		output /= 10;
		n++;
	}
	for (n--; n >= 0; n--)
	{
		putchar(buf[n] + '0');
	}
	return;
}
template<class T>
void ckmin(T &a, T b)
{
	a = min(a, b);
}
template<class T>
void ckmax(T &a, T b)
{
	a = max(a, b);
}
long long expo(long long a, long long e, long long mod)
{
	return ((e == 0) ? 1 : ((expo(a * a % mod, e >> 1, mod)) * ((e & 1) ? a : 1) % mod));
}
template<class T, class U>
void nmod(T &x, U mod)
{
	if (x >= mod) x -= mod;
}
template<class T>
T gcd(T a, T b)
{
	return (b ? gcd(b, a % b) : a);
}
template<class T>
T randomize(T mod)
{
	return (uniform_int_distribution<T>(0, mod - 1))(rng);
}

#define y0 ___y0
#define y1 ___y1
#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define DBG(x) cerr << #x << " = " << x << endl
#define SZ(x) ((int) (x.size()))
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)
#define ALL(x) x.begin(), x.end()

const long double PI = 4.0 * atan(1.0);
const long double EPS = 1e-9;

#define MAGIC 347
#define SINF 10007
#define CO 1000007
#define INF 1000000007
#define BIG 1000000931
#define LARGE 1696969696967ll
#define GIANT 2564008813937411ll
#define LLINF 2696969696969696969ll
#define MAXN 100013
#define MAXK 113

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ld, ld> pdd;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<ld> vd;
typedef vector<pii> vpi;
typedef vector<pll> vpl;
typedef vector<pdd> vpd;

int N, K;
ll arr[MAXN];
int parent[MAXN];
vi edge[MAXN];
ll sum[MAXN];
ll dup[MAXN][MAXK], ddn[MAXN][MAXK];
ll ans;
vector<int> ord;

void dfs(int u)
{
	for (int v : edge[u])
	{
		if (v == parent[u]) continue;
		parent[v] = u;
		dfs(v);
	}
	ord.PB(u);
}
void solve(int u)
{
	pair<pll, pll> UP[MAXK], DN[MAXK];
	UP[0] = {{0, -1}, {0, -2}};
	FOR(i, 1, K + 1) UP[i] = {{sum[u], -1}, {0, -1}};
	FOR(i, 0, K + 1) DN[i] = {{0, -3}, {0, -4}};
	for (int v : edge[u])
	{
		if (v == parent[u]) continue;
		FOR(i, 1, K + 1)
		{
			//don't take it!
			pll poss = {max(dup[v][i - 1] + (sum[u] - arr[v]), dup[v][i]), v};
			if (poss > UP[i].fi)
			{
				UP[i].se = UP[i].fi;
				UP[i].fi = poss;
			}
			else if (poss > UP[i].se)
			{
				UP[i].se = poss;
			}
		}
		FOR(i, 1, K + 1)
		{
			//don't take it!
			pll poss = {max(ddn[v][i - 1] + (sum[v] - arr[u]), ddn[v][i]), v};
			if (poss > DN[i].fi)
			{
				DN[i].se = DN[i].fi;
				DN[i].fi = poss;
			}
			else if (poss > DN[i].se)
			{
				DN[i].se = poss;
			}
		}
	}
	FOR(i, 1, K + 1)
	{
		vector<pll> guys;
		guys.PB(UP[i].fi); guys.PB(UP[i].se); guys.PB(UP[i - 1].fi); guys.PB(UP[i - 1].se);
		pair<pll, pll> best = {{-INF, -INF}, {-INF, -INF}};
		FOR(i, 0, 4)
		{
			FOR(j, 0, 4)
			{
				if (guys[i].se == guys[j].se) continue;
				pair<pll, pll> cur = {{guys[i].fi, guys[j].fi}, {guys[i].se, guys[j].se}};
				ckmax(best, cur);
			}
		}
		UP[i] = {{best.fi.fi, best.se.fi}, {best.fi.se, best.se.se}};
		guys.clear();
		guys.PB(DN[i].fi); guys.PB(DN[i].se); guys.PB(DN[i - 1].fi); guys.PB(DN[i - 1].se);
		best = {{-INF, -INF}, {-INF, -INF}};
		FOR(i, 0, 4)
		{
			FOR(j, 0, 4)
			{
				if (guys[i].se == guys[j].se) continue;
				pair<pll, pll> cur = {{guys[i].fi, guys[j].fi}, {guys[i].se, guys[j].se}};
				ckmax(best, cur);
			}
		}
		DN[i] = {{best.fi.fi, best.se.fi}, {best.fi.se, best.se.se}};
	}
	FOR(i, 0, K + 1)
	{
		auto p = UP[i], p1 = DN[K - i];
		if (p.fi.se != p1.fi.se)
		{
			ckmax(ans, p.fi.fi + p1.fi.fi);
		}
		if (p.fi.se != p1.se.se)
		{
			ckmax(ans, p.fi.fi + p1.se.fi);
		}
		if (p.se.se != p1.fi.se)
		{
			ckmax(ans, p.se.fi + p1.fi.fi);
		}
	}
	FOR(i, 0, K + 1)
	{
		dup[u][i] = UP[i].fi.fi;
		ddn[u][i] = DN[i].fi.fi;
	}
	//solve it for up!
}

int32_t main()
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	// cout << fixed << setprecision(10);
	// cerr << fixed << setprecision(10);
	// if (fopen("file.in", "r"))
	// {
		// freopen ("file.in", "r", stdin);
		// freopen ("file.out", "w", stdout);
	// }
	cin >> N >> K;
	FOR(i, 0, N)
	{
		cin >> arr[i];
	}
	FOR(i, 0, N - 1)
	{
		int u, v;
		cin >> u >> v; u--; v--;
		edge[u].PB(v);
		edge[v].PB(u);
	}
	FOR(u, 0, N)
	{
		for (int v : edge[u])
		{
			sum[u] += arr[v];
		}
	}
	parent[0] = N;
	dfs(0);
	//S_(v_j) - A(v_(j-1))
	for (int u : ord)
	{
		solve(u);
	}
	cout << ans << '\n';
	// cerr << "time elapsed = " << (clock() / (CLOCKS_PER_SEC / 1000)) << " ms" << endl;
	return 0;
}
/* READ READ READ
* int overflow, maxn too small, special cases (n=1?, two distinct?), cin.tie() interactive
* reread the problem, try small cases
* do smth instead of nothing
*/

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2808 KB Output is correct
2 Correct 4 ms 2928 KB Output is correct
3 Correct 4 ms 2928 KB Output is correct
4 Correct 4 ms 2928 KB Output is correct
5 Correct 4 ms 2928 KB Output is correct
6 Correct 4 ms 2928 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2808 KB Output is correct
2 Correct 4 ms 2928 KB Output is correct
3 Correct 4 ms 2928 KB Output is correct
4 Correct 4 ms 2928 KB Output is correct
5 Correct 4 ms 2928 KB Output is correct
6 Correct 4 ms 2928 KB Output is correct
7 Correct 30 ms 4868 KB Output is correct
8 Correct 8 ms 4868 KB Output is correct
9 Correct 8 ms 4992 KB Output is correct
10 Correct 32 ms 4992 KB Output is correct
11 Correct 15 ms 4992 KB Output is correct
12 Correct 9 ms 4992 KB Output is correct

Subtask #3
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 2732 ms 188968 KB Output is correct
2 Correct 2732 ms 191136 KB Output is correct
3 Correct 2617 ms 192352 KB Output is correct
4 Correct 332 ms 194136 KB Output is correct
5 Correct 2883 ms 196408 KB Output is correct
6 Correct 2932 ms 198732 KB Output is correct
7 Correct 2882 ms 200672 KB Output is correct

Subtask #4
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 2808 KB Output is correct
2 Correct 4 ms 2928 KB Output is correct
3 Correct 4 ms 2928 KB Output is correct
4 Correct 4 ms 2928 KB Output is correct
5 Correct 4 ms 2928 KB Output is correct
6 Correct 4 ms 2928 KB Output is correct
7 Correct 30 ms 4868 KB Output is correct
8 Correct 8 ms 4868 KB Output is correct
9 Correct 8 ms 4992 KB Output is correct
10 Correct 32 ms 4992 KB Output is correct
11 Correct 15 ms 4992 KB Output is correct
12 Correct 9 ms 4992 KB Output is correct
13 Correct 2732 ms 188968 KB Output is correct
14 Correct 2732 ms 191136 KB Output is correct
15 Correct 2617 ms 192352 KB Output is correct
16 Correct 332 ms 194136 KB Output is correct
17 Correct 2883 ms 196408 KB Output is correct
18 Correct 2932 ms 198732 KB Output is correct
19 Correct 2882 ms 200672 KB Output is correct
20 Correct 2864 ms 202864 KB Output is correct
21 Correct 227 ms 204816 KB Output is correct
22 Correct 2836 ms 206904 KB Output is correct
23 Correct 274 ms 209068 KB Output is correct
24 Correct 2878 ms 211228 KB Output is correct
25 Correct 2624 ms 213148 KB Output is correct
26 Correct 2728 ms 216168 KB Output is correct
27 Correct 2720 ms 218216 KB Output is correct