oj.uz

Submission #900241

# Submission time Handle Problem Language Result Execution time Memory
900241 2024-01-08T00:15:54 Z starchan Sequence (APIO23_sequence) C++17
100 / 100
 904 ms 103832 KB 
#include "sequence.h"
#include<bits/stdc++.h>
using namespace std;
#define in pair<int, int>
#define f first
#define s second
#define pb push_back
#define pob pop_back
#define INF (int)1e6
#define MX (int)3e5+5
#define fast() ios_base::sync_with_stdio(false); cin.tie(NULL)
in extremise(const in &a, const in&b)
{
	return {min(a.f, b.f), max(a.s, b.s)};
}
void increment(int delta, in &a)
{
	if(a.f == INF)
		return;
	a.f+=delta;
	a.s+=delta;
	return;
}
struct extremal_tree
{
	vector<in> tree;
	void init(int n)
	{
		tree.assign(4*n+8, {INF, -INF});
		return;
	}
	void upd(int v, int pos, int id, int l, int r)
	{
		if(l == r)
		{
			tree[id] = extremise(tree[id], {v, v});
			return;
		}
		int m = (l+r)/2;
		if(pos <= m)
			upd(v, pos, 2*id, l, m);
		else
			upd(v, pos, 2*id+1, m+1, r);
		tree[id] = extremise(tree[2*id], tree[2*id+1]);
		return;
	}
	in val(int ql, int qr, int id, int l, int r)
	{
		if(r < ql || qr < l)
			return {INF, -INF};
		if(ql <= l && r <= qr)
			return tree[id];
		int m = (l+r)/2;
		in a = val(ql, qr, 2*id, l, m);
		in b = val(ql, qr, 2*id+1, m+1, r);
		return extremise(a, b);
	}
};
struct lazy_extremal_tree
{
	vector<in> tree;
	vector<int> lazy;
	void init(int n)
	{
		tree.assign(4*n+8, {INF, -INF});
		lazy.assign(4*n+8, 0);
		return;
	}
	void push(int id)
	{
		increment(lazy[id], tree[2*id]);
		increment(lazy[id], tree[2*id+1]);
		lazy[2*id]+=lazy[id];
		lazy[2*id+1]+=lazy[id];
		lazy[id] = 0;
		return;
	}
	void upd(int v, int pos, int id, int l, int r)
	{
		if(l == r)
		{
			tree[id] = extremise(tree[id], {v, v});
			return;
		}
		int m = (l+r)/2;
		if(pos <= m)
			upd(v, pos, 2*id, l, m);
		else
			upd(v, pos, 2*id+1, m+1, r);
		tree[id] = extremise(tree[2*id], tree[2*id+1]);
		return;
	}
	void upd2(int delta, int ql, int qr, int id, int l, int r)
	{
		if(qr < l || r < ql)
			return;
		if(ql <= l && r <= qr)
		{
			lazy[id]+=delta;
			increment(delta, tree[id]);
			return;
		}
		push(id);
		int m = (l+r)/2;
		upd2(delta, ql, qr, 2*id, l, m);
		upd2(delta, ql, qr, 2*id+1, m+1, r);
		tree[id] = extremise(tree[2*id], tree[2*id+1]);
		return;
	}
	in val(int ql, int qr, int id, int l, int r)
	{
		if(r < ql || qr < l)
			return {INF, -INF};
		if(ql <= l && r <= qr)
			return tree[id];
		push(id);
		int m = (l+r)/2;
		in a = val(ql, qr, 2*id, l, m);
		in b = val(ql, qr, 2*id+1, m+1, r);
		return extremise(a, b);
	}
};

vector<int> compressor;
int compress(int n)
{
	return lower_bound(compressor.begin(), compressor.end(), n)-compressor.begin();
}
int solve(int n, vector<in> &ac, vector<in> &bd)//no assuming compression!
{
	extremal_tree work;
	compressor.clear();
	work.init(2*n);
	vector<int> v;
	
	//compress begin
	for(auto [a, c]: ac)
		v.pb(c);
	for(auto [b, d]: bd)
		v.pb(d);
	sort(v.begin(), v.end());
	compressor.pb(v[0]);
	for(int k = 1; k < v.size(); k++)
	{
		if(v[k] != v[k-1])
			compressor.pb(v[k]);
	}
	//compress over

	vector<in> a;
	vector<in> b;
	for(int i = 0; i < n; i++)
		a.pb({ac[i].f, i});
	for(int i = 0; i < n; i++)
		b.pb({bd[i].f, i});
	sort(a.begin(), a.end());
	sort(b.begin(), b.end());
	
	int ans = -INF;

	int l = 0;
	for(int i = 0; i < n; i++)
	{
		while((l < n) && (a[l].f <= b[i].f))
		{
			work.upd(a[l].s, compress(ac[a[l].s].s), 1, 0, 2*n);
			l++;
		}
		auto [m, M] = work.val(0, compress(bd[b[i].s].s), 1, 0, 2*n);
		if(m != INF)
			ans = max(abs(m-b[i].s), ans);
		if(M != -INF)
			ans = max(abs(M-b[i].s), ans);
	}
	return ans;
}



int sequence(int n, vector<int> a)
{
	lazy_extremal_tree work;
	work.init(n);
	vector<int> adj[n+1];
	for(int i = 1; i <= n; i++)
		adj[a[i-1]].pb(i);
	for(int i = 0; i <= n; i++)
		work.upd(-i, i, 1, 0, n);
	int ans = 0;
	for(int i = 1; i <= n; i++)
	{
		int m = adj[i].size();
		for(int k: adj[i-1])
			work.upd2(+1, k, n, 1, 0, n);
		for(int k: adj[i])
			work.upd2(+1, k, n, 1, 0, n);
		vector<int> bb(m+2);
		bb[0] = 0;
		bb[m+1] = n+1;
		for(int j = 1; j <= m; j++)
			bb[j] = adj[i][j-1];
		vector<in> ac(m+1), bd(m+1);
		for(int j = 0; j <= m; j++)
		{
			auto [a, b] = work.val(bb[j], bb[j+1]-1, 1, 0, n);
			ac[j] = {a+j, j-b};
			bd[j] = {b+j, j-a};
		}
		int ok = solve(m+1, ac, bd);
		ans = max(ans, ok);
	}
	return ans;
}

/*vector<int> c;
int W(int l, int r, int x)
{
	int cnt = 0;
	for(int i = l; i <= r; i++)
		cnt+=(c[i] == x);
	return cnt;
}
int median_freq(int l, int r)
{
	vector<int> v;
	int k = r-l;
	for(int i = l; i <= r; i++)
		v.pb(c[i]);
	sort(v.begin(), v.end());
	int t = k/2;
	int tp = t+k%2;
	return max(W(l, r, v[t]), W(l, r, v[tp]));
}

signed main()
{
	fast();
	int t;
	cin >> t;
	while(t--)
	{
		c.clear();
		int n;
		cin >> n;
		vector<int> a(n);
		for(int &k: a)
		{
			cin >> k;
			c.pb(k);
		}
		int ans = sequence(n, a);
		int tit = 0;
		for(int l = 0; l < n; l++)
		{
			for(int r = l; r < n; r++)
				tit = max(tit, median_freq(l, r));
		}
		if(ans != tit)
		{
			cout << "WTF !!!" << endl;
			printf("Fake = %d, real = %d", ans, tit);
		}
		assert(ans==tit);
		cout << "All good!" << endl;
	}
	return 0;
}*/

Compilation message

sequence.cpp: In function 'int solve(int, std::vector<std::pair<int, int> >&, std::vector<std::pair<int, int> >&)':
sequence.cpp:143:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  143 |  for(int k = 1; k < v.size(); k++)
      |                 ~~^~~~~~~~~~

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 428 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 428 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 4 ms 604 KB Output is correct
14 Correct 3 ms 604 KB Output is correct
15 Correct 3 ms 628 KB Output is correct
16 Correct 3 ms 600 KB Output is correct
17 Correct 3 ms 856 KB Output is correct
18 Correct 2 ms 604 KB Output is correct
19 Correct 3 ms 604 KB Output is correct
20 Correct 3 ms 604 KB Output is correct
21 Correct 3 ms 604 KB Output is correct
22 Correct 3 ms 604 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 652 ms 52812 KB Output is correct
3 Correct 664 ms 52812 KB Output is correct
4 Correct 747 ms 54688 KB Output is correct
5 Correct 662 ms 51792 KB Output is correct
6 Correct 637 ms 51788 KB Output is correct
7 Correct 677 ms 44792 KB Output is correct
8 Correct 687 ms 44844 KB Output is correct
9 Correct 753 ms 64396 KB Output is correct

Subtask #4
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 783 ms 82240 KB Output is correct
3 Correct 777 ms 63568 KB Output is correct
4 Correct 783 ms 65600 KB Output is correct
5 Correct 754 ms 79104 KB Output is correct
6 Correct 710 ms 73180 KB Output is correct

Subtask #5
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 804 ms 58704 KB Output is correct
2 Correct 812 ms 58428 KB Output is correct
3 Correct 792 ms 57940 KB Output is correct
4 Correct 818 ms 57928 KB Output is correct
5 Correct 734 ms 54520 KB Output is correct
6 Correct 724 ms 54612 KB Output is correct
7 Correct 666 ms 53572 KB Output is correct
8 Correct 665 ms 53040 KB Output is correct

Subtask #6
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 428 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 4 ms 604 KB Output is correct
14 Correct 3 ms 604 KB Output is correct
15 Correct 3 ms 628 KB Output is correct
16 Correct 3 ms 600 KB Output is correct
17 Correct 3 ms 856 KB Output is correct
18 Correct 2 ms 604 KB Output is correct
19 Correct 3 ms 604 KB Output is correct
20 Correct 3 ms 604 KB Output is correct
21 Correct 3 ms 604 KB Output is correct
22 Correct 3 ms 604 KB Output is correct
23 Correct 114 ms 8792 KB Output is correct
24 Correct 117 ms 8540 KB Output is correct
25 Correct 115 ms 8540 KB Output is correct
26 Correct 116 ms 7516 KB Output is correct
27 Correct 112 ms 7624 KB Output is correct
28 Correct 127 ms 7688 KB Output is correct
29 Correct 112 ms 9124 KB Output is correct
30 Correct 117 ms 9388 KB Output is correct
31 Correct 132 ms 17228 KB Output is correct
32 Correct 97 ms 9660 KB Output is correct
33 Correct 118 ms 9808 KB Output is correct
34 Correct 118 ms 9588 KB Output is correct
35 Correct 116 ms 9808 KB Output is correct
36 Correct 117 ms 10064 KB Output is correct
37 Correct 122 ms 9812 KB Output is correct
38 Correct 126 ms 9840 KB Output is correct

Subtask #7
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 428 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 4 ms 604 KB Output is correct
14 Correct 3 ms 604 KB Output is correct
15 Correct 3 ms 628 KB Output is correct
16 Correct 3 ms 600 KB Output is correct
17 Correct 3 ms 856 KB Output is correct
18 Correct 2 ms 604 KB Output is correct
19 Correct 3 ms 604 KB Output is correct
20 Correct 3 ms 604 KB Output is correct
21 Correct 3 ms 604 KB Output is correct
22 Correct 3 ms 604 KB Output is correct
23 Correct 652 ms 52812 KB Output is correct
24 Correct 664 ms 52812 KB Output is correct
25 Correct 747 ms 54688 KB Output is correct
26 Correct 662 ms 51792 KB Output is correct
27 Correct 637 ms 51788 KB Output is correct
28 Correct 677 ms 44792 KB Output is correct
29 Correct 687 ms 44844 KB Output is correct
30 Correct 753 ms 64396 KB Output is correct
31 Correct 783 ms 82240 KB Output is correct
32 Correct 777 ms 63568 KB Output is correct
33 Correct 783 ms 65600 KB Output is correct
34 Correct 754 ms 79104 KB Output is correct
35 Correct 710 ms 73180 KB Output is correct
36 Correct 804 ms 58704 KB Output is correct
37 Correct 812 ms 58428 KB Output is correct
38 Correct 792 ms 57940 KB Output is correct
39 Correct 818 ms 57928 KB Output is correct
40 Correct 734 ms 54520 KB Output is correct
41 Correct 724 ms 54612 KB Output is correct
42 Correct 666 ms 53572 KB Output is correct
43 Correct 665 ms 53040 KB Output is correct
44 Correct 114 ms 8792 KB Output is correct
45 Correct 117 ms 8540 KB Output is correct
46 Correct 115 ms 8540 KB Output is correct
47 Correct 116 ms 7516 KB Output is correct
48 Correct 112 ms 7624 KB Output is correct
49 Correct 127 ms 7688 KB Output is correct
50 Correct 112 ms 9124 KB Output is correct
51 Correct 117 ms 9388 KB Output is correct
52 Correct 132 ms 17228 KB Output is correct
53 Correct 97 ms 9660 KB Output is correct
54 Correct 118 ms 9808 KB Output is correct
55 Correct 118 ms 9588 KB Output is correct
56 Correct 116 ms 9808 KB Output is correct
57 Correct 117 ms 10064 KB Output is correct
58 Correct 122 ms 9812 KB Output is correct
59 Correct 126 ms 9840 KB Output is correct
60 Correct 904 ms 52812 KB Output is correct
61 Correct 873 ms 52800 KB Output is correct
62 Correct 880 ms 52816 KB Output is correct
63 Correct 799 ms 44880 KB Output is correct
64 Correct 808 ms 44748 KB Output is correct
65 Correct 802 ms 44748 KB Output is correct
66 Correct 764 ms 55068 KB Output is correct
67 Correct 768 ms 54820 KB Output is correct
68 Correct 773 ms 103832 KB Output is correct
69 Correct 666 ms 58536 KB Output is correct
70 Correct 895 ms 58804 KB Output is correct
71 Correct 881 ms 60024 KB Output is correct
72 Correct 841 ms 60624 KB Output is correct
73 Correct 869 ms 60392 KB Output is correct
74 Correct 848 ms 62272 KB Output is correct
75 Correct 858 ms 60044 KB Output is correct