oj.uz

Submission #753794

# Submission time Handle Problem Language Result Execution time Memory
753794 2023-06-06T04:15:10 Z blue Radio Towers (IOI22_towers) C++17
0 / 100
 1712 ms 16468 KB 
#include "towers.h"
#include <bits/stdc++.h>
using namespace std;

using vi = vector<int>;
using vvi = vector<vi>;
using ll = long long;
using vll = vector<ll>;

int N;
vi H;

vi LS, RS;

vll dist, dist2;







struct segtree
{
	int l;
	int r;

	int mx = 0;


	segtree* left = NULL;
	segtree* right = NULL;

	segtree()
	{
		;
	}

	segtree(int L, int R)
	{
		l = L;
		r = R;

		if(l == r)
			mx = H[l];
		else
		{
			int m = (l + r)/2;
			left = new segtree(l, m);
			right = new segtree(m+1, r);

			mx = max(left->mx, right->mx);
		}
	}

	int rangemax(int L, int R)
	{
		if(R < l || r < L)
			return -1;
		else if(L <= l && r <= R)
			return mx;
		else
			return max(left->rangemax(L, R), right->rangemax(L, R));
	}
};









void init(int N_, vi H_)
{
	N = N_;
	H = H_;

	LS = RS = vi(N, -1);

	vi st;
	st.push_back(-1);

	for(int i = 0; i < N; i++)
	{
		while(st.back() != -1 && H[i] < H[st.back()])
			st.pop_back();

		LS[i] = st.back();

		st.push_back(i);
	}


	segtree ST(0, N-1);


	st.clear();

	st.push_back(N);
	for(int i = N-1; i >= 0; i--)
	{
		while(st.back() != N && H[i] < H[st.back()])
			st.pop_back();

		RS[i] = st.back();

		st.push_back(i);
	}

	for(int i = 0; i < N; i++)
	{
		dist.push_back(0);

		ll lval = 1'000'000'001LL;

		if(LS[i] != -1)
			lval = ST.rangemax(LS[i]+1, i-1);



		ll rval = 1'000'000'001LL;

		if(RS[i] != N)
			rval = ST.rangemax(i+1, RS[i]-1);


		dist[i] = min(lval, rval);

		cerr << i << " : " << LS[i] << ' ' << RS[i] << ' ' << lval << ' ' << rval << '\n';
	}

	dist2 = dist;

	sort(dist2.begin(), dist2.end());
}

int max_towers(int L, int R, int D)
{
	int lo = 0, hi = N;
	while(lo != hi)
	{
		int mid = (lo + hi)/2;

		if(dist2[mid] < D)
			lo = mid+1;
		else
			hi = mid;
	}

	return N - lo;
}

Subtask #1
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 999 ms 10428 KB 1st lines differ - on the 1st token, expected: '1', found: '2'
2 Halted 0 ms 0 KB -

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 336 KB 1st lines differ - on the 1st token, expected: '13', found: '140'
2 Halted 0 ms 0 KB -

Subtask #3
0 / 12.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 336 KB 1st lines differ - on the 1st token, expected: '13', found: '140'
2 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 1712 ms 16468 KB 1st lines differ - on the 1st token, expected: '11903', found: '33010'
2 Halted 0 ms 0 KB -

Subtask #5
0 / 17.0

# Verdict Execution time Memory Grader output
1 Incorrect 538 ms 4164 KB 1st lines differ - on the 1st token, expected: '7197', found: '7999'
2 Halted 0 ms 0 KB -

Subtask #6
0 / 19.0

# Verdict Execution time Memory Grader output
1 Incorrect 6 ms 336 KB 1st lines differ - on the 1st token, expected: '13', found: '140'
2 Halted 0 ms 0 KB -

Subtask #7
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 999 ms 10428 KB 1st lines differ - on the 1st token, expected: '1', found: '2'
2 Halted 0 ms 0 KB -