Submission #161996

#	Time	Username	Problem	Language	Result	Execution time	Memory
161996		nvmdava	Watching (JOI13_watching)	C++17	100 / 100	162 ms	16160 KiB

watching

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ff first
#define ss second
#define pb push_back
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define N 2005
#define INF 0x3f3f3f3f3f3f3f3f
#define MOD 1000000007LL

int a[N];
int dp[N][N];
int n, p, q;

bool check(int w){
	int l = 0, r = 0;
	for(int i = 1; i <= n; i++){
		while(a[i] - w >= a[l + 1])
			++l;
		while(a[i] - 2 * w >= a[r + 1])
			++r;
		dp[i][0] = dp[r][0] - 1;
		for(int j = 1; j <= p; j++){
			dp[i][j] = max(dp[l][j - 1], dp[r][j] - 1);
		}
	}
	return dp[n][p] >= 0;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin>>n>>p>>q;
    for(int i = 0; i <= p; i++)
    	dp[0][i] = q;
    if(p + q >= n){
    	cout<<1;
    	return 0;
    }

    for(int i = 1; i <= n; i++)
    	cin>>a[i];
    sort(a + 1, a + 1 + n);

    int l = 1, r = 1000000000;

    while(l != r){
    	int m = (l + r) >> 1;
    	if(check(m)) r = m;
    	else l = m + 1;
    }

    cout<<r;

}

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