For problem statement at 0-999/0-99/60-69/69/problemE.txt this is a correct solution, but verifier at 0-999/0-99/60-69/69/verifierE.go ends with All tests passed can you fix the verifier? ```go
package main
import (
"bufio"
"container/heap"
"fmt"
"os"
)
type IntHeap []int
func (h IntHeap) Len() int { return len(h) }
func (h IntHeap) Less(i, j int) bool { return h[i] > h[j] }
func (h IntHeap) Swap(i, j int) { h[i], h[j] = h[j], h[i] }
func (h *IntHeap) Push(x interface{}) {
*h = append(*h, x.(int))
}
func (h *IntHeap) Pop() interface{} {
old := *h
n := len(old)
x := old[n-1]
*h = old[0 : n-1]
return x
}
func main() {
r := bufio.NewReader(os.Stdin)
var n, k int
fmt.Fscan(r, &n, &k)
a := make([]int, n)
for i := 0; i < n; i++ {
fmt.Fscan(r, &a[i])
}
freq := make(map[int]int)
h := &IntHeap{}
heap.Init(h)
left := 0
for right := 0; right < n; right++ {
val := a[right]
freq[val]++
if freq[val] == 1 {
heap.Push(h, val)
}
if right-left+1 > k {
leftVal := a[left]
freq[leftVal]--
if freq[leftVal] == 1 {
heap.Push(h, leftVal)
}
if freq[leftVal] == 0 {
delete(freq, leftVal)
}
left++
}
if right >= k-1 {
for h.Len() > 0 && freq[(*h)[0]] != 1 {
heap.Pop(h)
}
if h.Len() == 0 {
fmt.Println("Nothing")
} else {
fmt.Println((*h)[0])
}
}
}
}
```