oj.uz

Submission #51450

# Submission time Handle Problem Language Result Execution time Memory
51450 2018-06-18T02:58:11 Z Vinhspm Watching (JOI13_watching) C++14
50 / 100
 1000 ms 8892 KB 
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define ii pair<int, int>
#define fi first
#define se second
#define pb push_back
const int N = 2009;
const int oo = 1e9;
const int mod = 1e9 + 7;
int n, P, Q;
int a[N], dp[N][N];
bool check(int x)	{
	// base
	for(int i = 0; i <= P; ++ i)
		for(int j = 0; j <= Q; ++j)
			dp[i][j] = -1;
	dp[0][0] = 0;
	for(int i = 0; i <= P; ++i)
		for(int j = 0; j <= Q; ++j){
				if(i > 0)	{
					int cur = dp[i - 1][j] + 1;
					int nexpos = a[cur] + x  - 1;
					int pos = upper_bound(a + 1, a + n + 1, nexpos) - a - 1;
					dp[i][j] = max(dp[i][j], pos);
				}
				if(j > 0)	{
					int cur = dp[i][j - 1] + 1;
					int nexpos = a[cur] + 2*x - 1;
					int pos = upper_bound(a + 1, a + n + 1, nexpos) - a - 1;
					dp[i][j] = max(dp[i][j], pos);
				}
				if(dp[i][j] == n) return true;
			}
	return false;
}
signed main()
{
	//freopen("test.txt", "r", stdin);
	//ios_base::sync_with_stdio(false);
	//cin.tie(0); cout.tie(0);
	scanf("%d%d%d", &n, &P, &Q);
	for(int i = 1; i <= n; ++i) scanf("%d", &a[i]);
	sort(a + 1, a + n + 1); a[0] = 0;
	if(P + Q >= n) {
		printf("1");
		return 0;
	}
	//cout << check(3) << '\n'; return 0;
	int l = 1, r = oo;
	while(r > l + 1)	{
		int mid = (l + r)/ 2;
		if(check(mid)) r = mid;
		else l = mid;
	}
	for(int i = l; i <= r; ++i)
		if(check(i))	{
			printf("%d", i); 
			return 0;
		}
}

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:42:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &n, &P, &Q);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
watching.cpp:43:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i = 1; i <= n; ++i) scanf("%d", &a[i]);
                              ~~~~~^~~~~~~~~~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 248 KB Output is correct
2 Correct 2 ms 356 KB Output is correct
3 Correct 2 ms 408 KB Output is correct
4 Correct 2 ms 408 KB Output is correct
5 Correct 2 ms 408 KB Output is correct
6 Correct 2 ms 536 KB Output is correct
7 Correct 2 ms 600 KB Output is correct
8 Correct 2 ms 600 KB Output is correct
9 Correct 2 ms 600 KB Output is correct
10 Correct 2 ms 600 KB Output is correct
11 Correct 3 ms 800 KB Output is correct
12 Correct 3 ms 800 KB Output is correct
13 Correct 2 ms 800 KB Output is correct
14 Correct 2 ms 800 KB Output is correct
15 Correct 2 ms 800 KB Output is correct

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 800 KB Output is correct
2 Correct 2 ms 800 KB Output is correct
3 Correct 2 ms 800 KB Output is correct
4 Correct 2 ms 800 KB Output is correct
5 Correct 2 ms 800 KB Output is correct
6 Correct 2 ms 800 KB Output is correct
7 Correct 3 ms 800 KB Output is correct
8 Correct 193 ms 1476 KB Output is correct
9 Correct 174 ms 3940 KB Output is correct
10 Correct 183 ms 8892 KB Output is correct
11 Correct 151 ms 8892 KB Output is correct
12 Execution timed out 1079 ms 8892 KB Time limit exceeded
13 Halted 0 ms 0 KB -