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+;

 int a[N],dp[N];

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

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

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