제출 #419609

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
419609		amunduzbaev	Watching (JOI13_watching)	C++14	100 / 100	527 ms	16200 KiB

watching

/* made by amunduzbaev */
 
//~ #include <ext/pb_ds/assoc_container.hpp>
//~ #include <ext/pb_ds/tree_policy.hpp>
#include "bits/stdc++.h"
 
using namespace std;
//~ using namespace __gnu_pbds;

#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define NeedForSpeed ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vv vector
#define mem(arr, v) memset(arr, v, sizeof arr)
//~ #define int long long
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii; 
typedef vector<int> vii;
typedef vector<pii> vpii;
template<class T> bool umin(T& a, const T& b) { return a > b ? a = b, true : false; }
template<class T> bool umax(T& a, const T& b) { return a < b ? a = b, true : false; }
template<int sz> using tut = array<int, sz>;
void usaco(string s) { freopen((s+".in").c_str(),"r",stdin);  
	freopen((s+".out").c_str(),"w",stdout); NeedForSpeed }
//~ template<class T> using oset = tree<T, 
//~ null_type, less_equal<T>, rb_tree_tag, 
//~ tree_order_statistics_node_update>;
 
const int N = 2e3+5;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);
 
#define MULTI 0
int n, m, k, s, t, q, ans, res, a[N];
int W[N], dw[N], dp[N][N];;

int rec(int i, int j){
	int& res = dp[i][j];
	if(~res) return res;
	if(i > n) return res = 0;
	res = rec(dw[i], j) + 1;
	if(j) umin(res, rec(W[i], j - 1));
	return res;
}

bool check(int w){ mem(dp, -1);
	int l = 1, r = 1;
	for(;r<=n;r++){
		while(a[r] - a[l] + 1 > w) W[l] = r, l++;
	} while(l <= n) W[l] = r, l++;
	l = 1, r = 1;
	for(;r<=n;r++){
		while(a[r] - a[l] + 1 > 2 * w) dw[l] = r, l++;
	} while(l <= n) dw[l] = r, l++;
	return (rec(1, m) <= q);
}

void solve(int t_case){
	cin>>n>>m>>q;
	for(int i=1;i<=n;i++) cin>>a[i];
	if(m + q > n) { cout<<1<<"\n"; return; }
	sort(a+1, a+n+1);
	a[0] = a[1];
	
	int l = 1, r = mod;
	while(l + 1 < r){
		int m = (l + r)>>1;
		if(check(m)) r = m;
		else l = m;
	} if(!check(l)) l = r;
	cout<<l<<"\n";
}

signed main(){
	NeedForSpeed
	if(MULTI){
		int t; cin>>t;
		for(int t_case = 1; t_case <= t; t_case++) solve(t_case);
	} else solve(1);
	return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

watching.cpp: In function 'void usaco(std::string)':
watching.cpp:32:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 | void usaco(string s) { freopen((s+".in").c_str(),"r",stdin);
      |                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
watching.cpp:33:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |  freopen((s+".out").c_str(),"w",stdout); NeedForSpeed }
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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