cf747 D. Winter Is Coming

天呢，这个题2333333，真是被各种卡。完蛋完蛋完蛋。IQ------------；

 #include<bits/stdc++.h>
 #define lowbit(x) x&(-x)
 #define LL long long
 #define N 100005
 #define M 1000005
 #define mod 2147483648LL
 #define inf 0x7ffffffff
 using namespace std;
 inline int ra()
 {
     int x=,f=; char ch=getchar();
     while (ch<'' || ch>''){if (ch=='-') f=-; ch=getchar();}
     while (ch>='' && ch<=''){x=x*+ch-''; ch=getchar();}
     return x*f;
 }
 int n,k,last,ans,cnt;
 int a[N<<],b[N<<];
 int main()
 {
     n=ra(); k=ra();
     for (int i=; i<=n; i++) a[i]=ra();
     int last,start=n+;
     for (int i=; i<=n; i++)
         if (a[i]<) {
             start=i;
             break;
         }
     if (start<=n) ans=,k--;
     else {
         cout<<"";
         return ;
     }
     for (int i=start+; i<=n; i++)
     {
         if (a[i]<) k--;
         if (a[i]>= && a[i-]<) last=i,ans++;
         if (a[i]>= && a[i+]<) b[++cnt]=i-last+,ans++;
     }
     if (k<)
     {
         cout<<"-1";
         return ;
     }
     sort(b+,b+cnt+);
     for (int i=; i<=cnt; i++)
         if (k-b[i]<) break;
             else k-=b[i],ans-=;
     if (a[n]>=)
         for (int i=n; i>=; i--)
             if (a[i]<)
             {
                 b[++cnt]=n-i;
                 break;
             }
     if (b[cnt]<=k && cnt) ans--;
     cout<<ans;
     return ;
 }