light oj 1084 线性dp

#include <iostream>
#include <algorithm>
#include <cstring>
#include <cstdio>
#include <queue>
#define ll long long

using namespace std;
const int N = 1e5+1000;

int a
,dp
;

void solve()
{
int n,k;
scanf("%d %d",&n,&k);
for(int i = 0; i < n; i++)
{
scanf("%d",&a[i]);
}
sort(a,a+n);
memset(dp,0,sizeof(dp));
for(int i = n-1; i >= 0; i--)
{
dp[i] = 0x3f3f3f;
int j = upper_bound(a,a+n,a[i]+2*k)-a;
if(j - i >= 3) dp[i] = min(dp[j]+1,dp[i]);
if(j - i >= 4) dp[i] = min(dp[j-1]+1,dp[i]);
if(j - i >= 5) dp[i] = min(dp[j-2]+1,dp[i]);
}
if(dp[0] == 0x3f3f3f)
printf("-1\n");
else
printf("%d\n",dp[0]);
}

int main(void)
{
int t,cnt = 0;
scanf("%d",&t);

while(t--)
{
printf("Case %d: ",++cnt);
solve();
}
return 0;
}