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67 lines (50 loc) · 1.38 KB
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prims.py
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67 lines (50 loc) · 1.38 KB
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class MaxHeap:
def __init__(self,keys):
self.keys=[]
self.into=[]
self.outof=[]
def heap_smallest(self):
return self.keys[self.outof[0]]
def siftdown(self,i):
pass
def delete(self):
pass
def insert(self,val):
pass
def heapify(self):
pass
def decrease(self,index,val):
self.keys[index]=val
child=self.into[index]
parent=child/2
while(parent >=1):
if(self.keys[self.outof[p]]<=val):
break
self.outof[c]=self.outof[parent]
self.into[self.outof[child]]=child
#move p and c up
child=parent
parent=child/2
self.outof[child]=i
self.into[i]=child
class Keeper:
def __init__(self,keys):
self.keys={i:e for i,e enumerated(keys) }
def delete(self,key):
val=self.keys[key]
self.keys.delete(key)
def decrease(self,w,wgt):
self.keys[w]=wgt
def isin(self,w):
return w in self.keys
def keyval(self,w):
return self.keys[w]
def prims(adj,start,parent):
keys=[ -1 for in range(1,len(adj))]
keys[start]=0
parent=[]
parent[start]=0
h=Keeper(keys)
for i in range(1,len(adj)):
v=h.delete()
ref=adj[v]