<reponame>shawlu95/Algorithm-Toolbox
class MaxHeap:
    def __init__(self):
        self.heapList = [0]
        self.currentSize = 0

    def percUp(self, i):
        while i // 2 > 0:
            if self.heapList[i] > self.heapList[i // 2]:
                self.heapList[i], self.heapList[i // 2] = self.heapList[i // 2], self.heapList[i]
                print(self.heapList)
            i = i // 2

    def insert(self, k):
        self.heapList.append(k)
        self.currentSize = self.currentSize + 1
        self.percUp(self.currentSize)

    def percDown(self, i):
        while (i * 2) <= self.currentSize:
            mc = self.maxChild(i)
            if self.heapList[i] < self.heapList[mc]:
                self.heapList[i], self.heapList[mc] = self.heapList[mc], self.heapList[i]
                print(self.heapList)
            i = mc

    def maxChild(self, i):
        if i * 2 + 1 > self.currentSize:
            return i * 2
        else:
            if self.heapList[i * 2] > self.heapList[i * 2 + 1]:
                return i * 2
            else:
                return i * 2 + 1

    def delMax(self):
        retval = self.heapList[1]
        self.heapList[1] = self.heapList[self.currentSize]
        self.currentSize = self.currentSize - 1
        self.heapList.pop()
        self.percDown(1)
        return retval

    def buildHeap(self, alist):
        i = len(alist) // 2
        self.currentSize = len(alist)
        self.heapList = [0] + alist[:]
        while i > 0:
            self.percDown(i)
            i = i - 1

print("\nBuild heap")
heap = MaxHeap()
heap.buildHeap([2, 3, 5, 6, 9])

print("\nInsert small")
print(heap.heapList)
heap.insert(1)
print(heap.heapList)

print("\nInsert large")
print(heap.heapList)
heap.insert(8)

print("\nDelete max")
print(heap.heapList)
heap.delMax()
print(heap.heapList)
class MaxHeap:
    def __init__(self):
        self.heapList = [0]
        self.currentSize = 0

    def percUp(self, i):
        while i // 2 > 0:
            if self.heapList[i] > self.heapList[i // 2]:
                self.heapList[i], self.heapList[i // 2] = self.heapList[i // 2], self.heapList[i]
                print(self.heapList)
            i = i // 2

    def insert(self, k):
        self.heapList.append(k)
        self.currentSize = self.currentSize + 1
        self.percUp(self.currentSize)

    def percDown(self, i):
        while (i * 2) <= self.currentSize:
            mc = self.maxChild(i)
            if self.heapList[i] < self.heapList[mc]:
                self.heapList[i], self.heapList[mc] = self.heapList[mc], self.heapList[i]
                print(self.heapList)
            i = mc

    def maxChild(self, i):
        if i * 2 + 1 > self.currentSize:
            return i * 2
        else:
            if self.heapList[i * 2] > self.heapList[i * 2 + 1]:
                return i * 2
            else:
                return i * 2 + 1

    def delMax(self):
        retval = self.heapList[1]
        self.heapList[1] = self.heapList[self.currentSize]
        self.currentSize = self.currentSize - 1
        self.heapList.pop()
        self.percDown(1)
        return retval

    def buildHeap(self, alist):
        i = len(alist) // 2
        self.currentSize = len(alist)
        self.heapList = [0] + alist[:]
        while i > 0:
            self.percDown(i)
            i = i - 1

print("\nBuild heap")
heap = MaxHeap()
heap.buildHeap([2, 3, 5, 6, 9])

print("\nInsert small")
print(heap.heapList)
heap.insert(1)
print(heap.heapList)

print("\nInsert large")
print(heap.heapList)
heap.insert(8)

print("\nDelete max")
print(heap.heapList)
heap.delMax()
print(heap.heapList)