Submission #1274418

#	Time	Username	Problem	Language	Result	Execution time	Memory
1274418		nthvn	Rabbit Carrot (LMIO19_triusis)	C++20	63 / 100	59 ms	6824 KiB

triusis

#include "bits/stdc++.h"
using namespace std;
#define int long long

#define LOG(n) (63 - __builtin_clzll((n)))
#define fi first
#define se second
#define pii pair<int,int> 
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
#define pb push_back
#define ll long long
const int N = 2e5+5;
int n,m,a[N];
int dp[N], pos[N];

struct BIT{
	int bit[N];
	BIT(){
		memset(bit,0x3f,sizeof(bit));
	}
	void update(int i, int x){
		for(;i;i-=i&-i) bit[i]= min(bit[i],x);
	}
	int get(int i){
		int ans =1e9;
		for(;i<=n+1;i+=i&-i) ans=min(ans,bit[i]);
		return ans;
	}
}bit;

void precalc(){
	vector<int> v;
	for(int i=1;i<=n;i++){
		v.pb(a[i]-(i+1)*m);
	}
	sort(all(v));
	for(int i=1;i<=n+1;i++){
		pos[i]= lower_bound(all(v), a[i]-(i+1)*m)-v.begin()+1;
	}
}

signed main(){
	ios_base::sync_with_stdio(NULL);
	cin.tie(NULL);
	if(fopen("TASK.INP", "r")){
		freopen("TASK.INP", "r", stdin);
		freopen("TASK.OUT", "w", stdout);
	}
	cin>>n>>m;
	for(int i=1;i<=n;i++) cin>>a[i];
	if(a[1]>m){
		dp[1]=1;
		a[1]=m;
	}
	precalc();
	bit.update(pos[1], dp[1]-2);
	// cerr<<"\n";
	for(int i=2;i<=n+1;i++){
		dp[i]= bit.get(pos[i]) +i;
		bit.update(pos[i], dp[i]-(i+1));
	}
	
	cout<<dp[n+1];
	
	
}

Compilation message (stderr)

triusis.cpp: In function 'int main()':
triusis.cpp:47:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |                 freopen("TASK.INP", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
triusis.cpp:48:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |                 freopen("TASK.OUT", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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