oj.uz

Submission #553649

# Submission time Handle Problem Language Result Execution time Memory
553649 2022-04-26T12:59:23 Z QwertyPi Watching (JOI13_watching) C++14
50 / 100
 1000 ms 15996 KB 
#include <bits/stdc++.h>
#define N 2001
using namespace std;
 
int dp[N][N];
int W1[N], W2[N];
int n, p, q;
vector<int> a;
 
bool ok(int w){
	for(int i = 0; i <= n; i++) for(int j = 0; j <= n; j++) dp[i][j] = (1 << 30); dp[0][0] = 0;
	int w1 = 0, w2 = 0;
	for(int i = 1; i <= n; i++){
		while(w2 < n && a[w2] <= a[i - 1] - w * 2) w2++;
		while(w1 < n && a[w1] <= a[i - 1] - w) w1++;
		W1[i] = w1, W2[i] = w2;
	}
	for(int j = 0; j <= q; j++){
		for(int i = 1; i <= n; i++){
			if(j > 0) dp[i][j] = min(dp[i][j], dp[W2[i]][j - 1]);
			dp[i][j] = min(dp[i][j], dp[W1[i]][j] + 1);
		}
		for(int i = 1; i <= n; i++) dp[i][j + 1] = min(dp[i][j], dp[i][j + 1]);
	}
	return dp[n][q] <= p;
}
 
int main(){
	cin >> n >> p >> q;
	p += q - min(n / 2, q);
	p = min(n, p); q = min(n / 2, q);
	for(int i = 0; i < n; i++){
		int v; cin >> v;
		a.push_back(v);
	}
	sort(a.begin(), a.end());
	int l, r;
	for(l = 0, r = 1e9 + 1; l != r;){
		int m = (l + r) / 2;
		if(ok(m)){
			r = m;
		}else{
			l = m + 1;
		}
	}
	cout << l << endl;
}

Compilation message

watching.cpp: In function 'bool ok(int)':
watching.cpp:11:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   11 |  for(int i = 0; i <= n; i++) for(int j = 0; j <= n; j++) dp[i][j] = (1 << 30); dp[0][0] = 0;
      |  ^~~
watching.cpp:11:80: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   11 |  for(int i = 0; i <= n; i++) for(int j = 0; j <= n; j++) dp[i][j] = (1 << 30); dp[0][0] = 0;
      |                                                                                ^~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 724 KB Output is correct
2 Correct 1 ms 308 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 1 ms 724 KB Output is correct
5 Correct 2 ms 688 KB Output is correct
6 Correct 2 ms 688 KB Output is correct
7 Correct 1 ms 724 KB Output is correct
8 Correct 1 ms 768 KB Output is correct
9 Correct 2 ms 724 KB Output is correct
10 Correct 2 ms 724 KB Output is correct
11 Correct 2 ms 688 KB Output is correct
12 Correct 2 ms 724 KB Output is correct
13 Correct 1 ms 724 KB Output is correct
14 Correct 1 ms 696 KB Output is correct
15 Correct 1 ms 724 KB Output is correct

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 83 ms 15996 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Execution timed out 1089 ms 15956 KB Time limit exceeded
4 Halted 0 ms 0 KB -