Submission #1251845

#	Time	Username	Problem	Language	Result	Execution time	Memory
1251845		ilhan_arda	Watching (JOI13_watching)	C++20	0 / 100	14 ms	9284 KiB

watching

//~ #pragma GCC optimize("O3,unroll-loops")
//~ #pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define fi first
#define se second
#define pb push_back
#define endl "\n"
#define int long long
using namespace std;

typedef long long ll;
typedef pair<int, int> ii;
typedef tuple<int, int, int> iii;
const int inf  = INT_MAX;
const int mod  = 1e9+7;

int n, p, q, w;
int a[105], dp[105][105][105];
bool f(int ind, int A, int b){
	if(ind > n) return true;
	if(dp[ind][A][b] != -1) return (bool)dp[ind][A][b];
	//kucuk
	if(A){
		int ind2 = upper_bound(a+1, a+n+1, a[ind]+w-1) - a;
		//~ cout<<ind<<" .. "<<ind2<<" .. " << w<<endl;
		bool c = f(ind2, A-1, b);
		if(c)dp[ind][A][b] = 1;
		if(c)return true; 
	}
	if(b){
		int ind2 = upper_bound(a+1, a+n+1, a[ind]+w*2-1) - a;
		bool c = f(ind2, A, b-1);
		if(c)dp[ind][A][b] = 1;
		if(c)return true; 
	}
	dp[ind][A][b] = 0;
	return false;
}
bool check(int x){
	w = x;
	memset(dp, -1, sizeof(dp));
	return f(1, p, q);
}
int32_t main(){
	fast;
	cin>>n>>p>>q;
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}
	sort(a+1, a+n+1);
	//~ for(int i=1;i<=n;i++){
		//~ cout<<a[i]<<" ";
	//~ }
	if(p + q >= n){
		cout<<1<<endl;
	}
	int l = 1, r = 1e9;
	while(l<=r){
		int m = (l+r)/2;
		if(check(m)){
			 r = m-1;
		}
		else l = m+1;
	}
	cout<<l<<endl;
}






//https://usaco.org/current/current/index.php?page=viewproblem2&cpid=282 bunu coz




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• Subtask 1: 0 / 50
• Subtask 2: 0 / 50