oj.uz

Submission #59139

# Submission time Handle Problem Language Result Execution time Memory
59139 2018-07-20T16:46:12 Z RezwanArefin01 Watching (JOI13_watching) C++17
0 / 100
 147 ms 16896 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> ii; 

const int N = 2010; 
int n, p, q, a[N], dp[N][N], w;

int f(int pos, int tot) {
	if(pos == n) return 0; 
	int &ret = dp[pos][p]; 
	if(~ret) return ret; 
	ret = 1e9;
	int x = lower_bound(a + pos, a + n, a[pos] + w) - a;
	int y = lower_bound(a + pos, a + n, a[pos] + w  + w) - a;
	if(tot < p) ret = f(x, tot + 1); 
	return ret = min(ret, 1 + f(y, tot)); 
}
int main(int argc, char const *argv[]) {
	scanf("%d %d %d", &n, &p, &q); 
	for(int i = 0; i < n; i++) 
		scanf("%d", &a[i]); 
	p = min(p, n); 
	sort(a, a + n);
	int lo = 1, hi = 1e9, ans = -1; 
	while(lo <= hi) {
		w = lo + hi >> 1; 
		memset(dp, -1, sizeof dp); 
		if(f(0, 0) <= q) {
			ans = w, hi = w - 1; 
		} else lo = w + 1; 
	} printf("%d\n", ans);
}

Compilation message

watching.cpp: In function 'int main(int, const char**)':
watching.cpp:28:10: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   w = lo + hi >> 1; 
       ~~~^~~~
watching.cpp:21:7: 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:23:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &a[i]); 
   ~~~~~^~~~~~~~~~~~~

Subtask #1
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 86 ms 16248 KB Output is correct
2 Correct 147 ms 16468 KB Output is correct
3 Incorrect 78 ms 16468 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 95 ms 16652 KB Output is correct
2 Correct 97 ms 16652 KB Output is correct
3 Correct 125 ms 16792 KB Output is correct
4 Correct 110 ms 16792 KB Output is correct
5 Correct 112 ms 16848 KB Output is correct
6 Correct 108 ms 16896 KB Output is correct
7 Incorrect 139 ms 16896 KB Output isn't correct
8 Halted 0 ms 0 KB -