Submission #486022

#	Time	Username	Problem	Language	Result	Execution time	Memory
486022		Duy_e	Rabbit Carrot (LMIO19_triusis)	C++14	0 / 100	2 ms	332 KiB

triusis

#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
#define pii pair<long long, long long>
#define st first
#define nd second
#define file "test"
using namespace std;
const long long oo = 1e18;
const long long N = 2e5 + 5;

int n, m, a[N], dp[N], bit[N];
int SIZE;

vector <int> compress;

void upd(int idx, int val){
	while (idx > 0)
		bit[idx] = max(bit[idx], val),
		idx -= idx & -idx;
}

int get(int idx, int ans = 0){
	while (idx <= SIZE)
		ans = max(bit[idx], ans),
		idx += idx & -idx;
	return ans;
}

int find(int x){
	int l = 0, r = compress.size() - 1, mid, ans = 0;
	while (l <= r){
		mid = l + r >> 1;
		if (compress[mid] >= x)
			ans = mid + 1, r = mid - 1;
		else
			l = mid + 1;
	}

	return ans;
}
int main()
{
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	#ifndef ONLINE_JUDGE
		freopen(file".inp","r",stdin); freopen(file".out","w",stdout);
	#endif
	
	cin >> n >> m;

	compress.push_back(0); // current standing
	compress.push_back(0 + m); // current standing
	for (int i = 1; i <= n; i ++){
		cin >> a[i];

		compress.push_back(a[i]);
		compress.push_back(max(0, a[i] - m));
		compress.push_back(a[i] + m);
	}

// cordinate compression
	sort(compress.begin(), compress.end());
	compress.resize(unique(compress.begin(), compress.end()) - compress.begin());
	SIZE = compress.size() + 100;
	// -> erase duplicate elements

// PROCESS: key idea -> finding longest possible path = L -> ans = n - L

	for (int i = 1; i <= SIZE; i ++)
		bit[i] = -1e9;

	upd(find(0), 1);
	for (int i = 1; i <= n; i ++){
		int cur = find(max(0, a[i] - m));
		// cout << get(cur) + 1 << ' ';
		ll tmp = get(cur) + 1;

		if (tmp == 1) continue;
		upd(find(a[i]), tmp);
		// cout << cur << ' ';
	}	

	cout << n - get(1) + 1;

	return 0;
}	
/**  /\_/\
    (= ._.)
    / >0  \>1 
  ________________________
 / Brainstorming section /
/=======================/
---
===


===
**/
// Before submit: spot the visible bug by reading the code.

Compilation message (stderr)

triusis.cpp: In function 'int find(int)':
triusis.cpp:33:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   33 |   mid = l + r >> 1;
      |         ~~^~~
triusis.cpp: In function 'int main()':
triusis.cpp:46:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   46 |   freopen(file".inp","r",stdin); freopen(file".out","w",stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
triusis.cpp:46:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   46 |   freopen(file".inp","r",stdin); freopen(file".out","w",stdout);
      |                                  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 21
• Subtask 3: 0 / 28
• Subtask 4: 0 / 37