Submission #428605

#	Time	Username	Problem	Language	Result	Execution time	Memory
428605		errorgorn	Sparklers (JOI17_sparklers)	C++17	50 / 100	70 ms	4092 KiB

sparklers

#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define ii pair<ll,ll>
#define fi first
#define se second
#define endl '\n'

#define puf push_front
#define pof pop_front
#define pub push_back
#define pob pop_back
#define lb lower_bound
#define ub upper_bound

#define rep(x,s,e) for (auto x=s-(s>e);x!=e-(s>e);s<e?x++:x--)
#define all(x) (x).begin(),(x).end()
#define sz(x) (int) (x).size()

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int n,k,t;
ll arr[100005];

bool memo[1005][1005];

bool can(ll i){
	rep(x,0,1005) rep(y,0,1005) memo[x][y]=false;
	
	memo[k][k]=true;
	
	rep(x,0,n){
		rep(y,1,n-x+1){
			int l=y,r=y+x;
			
			if (arr[r]-arr[l]>2*i*x) memo[l][r]=false;
			if (memo[l][r]) memo[l-1][r]=memo[l][r+1]=true;
		}
	}
	
	return memo[1][n];
}

int main(){
	cin.tie(0);
	cout.tie(0);
	cin.sync_with_stdio(false);
	
	cin>>n>>k>>t;
	
	rep(x,1,n+1) cin>>arr[x];
	
	ll lo=-1,hi=1e9,mi;
	while (hi-lo>1){
		mi=hi+lo>>1;
		
		if (can(mi)) hi=mi;
		else lo=mi;
	}
	
	cout<<(hi+t-1)/t<<endl;
}

Compilation message (stderr)

sparklers.cpp: In function 'int main()':
sparklers.cpp:56:8: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   56 |   mi=hi+lo>>1;
      |      ~~^~~

• Subtask 1: 30 / 30
• Subtask 2: 20 / 20
• Subtask 3: 0 / 50