feat: progress

pkg/questions/kth_largest_element_in_stream/main.go

@@ -0,0 +1,51 @@
+package kthlargestelementinstream
+
+import (
+	"container/heap"
+)
+
+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 any) {
+	*h = append(*h, x.(int))
+}
+
+func (h IntHeap) Peek() int {
+	return h[0]
+}
+
+func (h *IntHeap) Pop() any {
+	old := *h
+	x := old[len(old)-1]
+	*h = old[:len(old)-1]
+	return x
+}
+
+type KthLargest struct {
+	k       int
+	largest IntHeap
+}
+
+func Constructor(k int, nums []int) KthLargest {
+	result := KthLargest{k, IntHeap{}}
+	heap.Init(&result.largest)
+
+	for _, n := range nums {
+		result.Add(n)
+	}
+
+	return result
+}
+
+func (this *KthLargest) Add(val int) int {
+	heap.Push(&this.largest, val)
+	if this.largest.Len() > this.k {
+		heap.Pop(&this.largest)
+	}
+
+	return this.largest.Peek()
+}