Submission #707943

# Submission time Handle Problem Language Result Execution time Memory
707943 2023-03-10T14:39:59 Z Dan4Life Watching (JOI13_watching) C++17
100 / 100
287 ms 16084 KB
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
const int mxN = (int)2e3+10;
const int LINF = (int)1e9;
int n, p, q;
int a[mxN], P[mxN], Q[mxN], v[mxN], dp[mxN][mxN];

bool work(int w){
	for(int i=2,j=1,k=1; i <= n; i++){
		v[i]=v[i-1]+a[i]-a[i-1];
		P[i]=upper_bound(v+1,v+i+1,v[i]-w)-begin(v)-1,
		Q[i]=upper_bound(v+1,v+i+1,v[i]-2*w)-begin(v)-1;
	}
	for(int i = 1; i <= n; i++){
		for(int j = 0; j <= q; j++){
			dp[i][j] = min(LINF, dp[P[i]][j]+1);
			if(j) dp[i][j] = min(dp[i][j], dp[Q[i]][j-1]);
		}
	}
	return dp[n][q]<=p;
}

int32_t main() {
	ios_base::sync_with_stdio(false); cin.tie(0);
	cin >> n >> p >> q;
	for(int i = 1; i <= n; i++) cin >> a[i];
	sort(a+1,a+n+1); v[1]=a[1];
	if(p+q>=n){cout<<1;return 0;}
	int l = 1, r = (int)1e9;
	while(l<r){
		int mid = (l+r)/2;
		if(work(mid)) r=mid;
		else l=mid+1;
	}
	cout << l;
}

Compilation message

watching.cpp: In function 'bool work(int)':
watching.cpp:13:14: warning: unused variable 'j' [-Wunused-variable]
   13 |  for(int i=2,j=1,k=1; i <= n; i++){
      |              ^
watching.cpp:13:18: warning: unused variable 'k' [-Wunused-variable]
   13 |  for(int i=2,j=1,k=1; i <= n; i++){
      |                  ^
# Verdict Execution time Memory Grader output
1 Correct 1 ms 724 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 340 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 724 KB Output is correct
8 Correct 1 ms 724 KB Output is correct
9 Correct 1 ms 724 KB Output is correct
10 Correct 1 ms 724 KB Output is correct
11 Correct 1 ms 724 KB Output is correct
12 Correct 1 ms 724 KB Output is correct
13 Correct 1 ms 724 KB Output is correct
14 Correct 2 ms 724 KB Output is correct
15 Correct 1 ms 724 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 7 ms 8276 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 10 ms 8404 KB Output is correct
8 Correct 109 ms 14164 KB Output is correct
9 Correct 25 ms 9300 KB Output is correct
10 Correct 20 ms 9064 KB Output is correct
11 Correct 287 ms 16084 KB Output is correct
12 Correct 140 ms 16024 KB Output is correct
13 Correct 9 ms 8528 KB Output is correct
14 Correct 8 ms 8472 KB Output is correct
15 Correct 8 ms 8404 KB Output is correct