Submission #26824

#	TimeUTC-0	Username	Problem	Language	Result	Execution time	Memory
26824	2017-07-06 07:42:40	szawinis	Watching (JOI13_watching)	C++14	100 / 100	276 ms	17828 KiB

watching

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#include <bits/stdc++.h>
using namespace std;
const int MAX = (2e3)+1, INF = 1e8;
int n, p, q, a[MAX], dp[MAX][MAX];
bool check(int len) {
  for(int i = 1, x = 1, y = 1; i <= n; i++) {
    while(a[i] - a[x] + 1 > len) x++;
    while(a[i] - a[y] + 1 > 2*len) y++;
    for(int j = 0; j <= min(p, n); j++) dp[i][j] = dp[y-1][j] + 1;
    for(int j = 1; j <= min(p, n); j++) dp[i][j] = min(dp[x-1][j-1], dp[i][j]);
  }
  bool ret = false;
  for(int j = 0; j <= min(p, n); j++) ret |= dp[n][j] <= q;
  return ret;
}
int main() {
  ios::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);
  int l = 1, r = 1e9;
  while(l < r) {
    int mid = l+r >> 1;
    if(check(mid)) r = mid;
    else l = mid+1;
  }
  cout << l;
}
 
 
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Compilation message (stderr)

watching.cpp: In function 'int main()':
watching.cpp:25:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid = l+r >> 1;
              ^

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