Submission #48681

#	Time	Username	Problem	Language	Result	Execution time	Memory
48681		Pajaraja	Watching (JOI13_watching)	C++17	100 / 100	487 ms	15564 KiB

watching

#include <bits/stdc++.h>
#define MAXN 2007
using namespace std;
int n,p,q,a[MAXN],dp[MAXN][MAXN];
int provera(int x)
{
	int t1=0,t2=0,t3=1;
	for(int i=1;i<=q;i++) dp[i][0]=1000000000;
	dp[0][0]=0;
	while(t3<=n)
	{
		while(t1<t3 && a[t3]-a[t1+1]>=2*x) t1++;
		while(t2<t3 && a[t3]-a[t2+1]>=x) t2++;
		for(int i=0;i<=q;i++) 
		{
			dp[i][t3]=1000000000;
			if(i>0) dp[i][t3]=min(dp[i-1][t1],dp[i][t3]);
			dp[i][t3]=min(dp[i][t2]+1,dp[i][t3]);
		}
		t3++;
	}
	for(int i=0;i<=q;i++) if(dp[i][n]<=p) return true;
	return false;
}
int binarna(int l,int r)
{
	if(l==r) return l;
	int s=(l+r)/2;
	if(provera(s)) return binarna(l,s);
	return binarna(s+1,r);
}
int main()
{
	scanf("%d%d%d",&n,&p,&q);
	if(p+q>=n) {printf("1"); return 0;}
	for(int i=1;i<=n;i++) scanf("%d",&a[i]);
	sort(a+1,a+n+1);
	a[0]=-1000000000;
	printf("%d",binarna(1,(a[n]-a[1])/(p+2*q)+1));
}

Compilation message (stderr)

watching.cpp: In function 'int main()':
watching.cpp:34:7: 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:36:29: 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 / 50
• Subtask 2: 50 / 50