Last active
October 5, 2016 17:04
-
-
Save buyoh/c1f6d5df75867c9f353a62e10679fed2 to your computer and use it in GitHub Desktop.
Ruby Heap
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
class Heap | |
def initialize(a=[],cp=Proc.new{|l,r|l<r}) | |
@data = a.sort | |
@cp = cp | |
end | |
def empty? | |
@data.empty? | |
end | |
def top | |
@data[0] | |
end | |
def pop | |
_swap(0,-1) | |
i=0 | |
while i*2+2 < @data.size | |
l = i*2 + 1 | |
r = i*2 + 2 | |
if r<@data.size-1 && @cp.(@data[r],@data[l]) | |
if @cp.(@data[r],@data[i]) | |
_swap(i,r) | |
i=r | |
else | |
break | |
end | |
else | |
if @cp.(@data[l],@data[i]) | |
_swap(i,l) | |
i=l | |
else | |
break | |
end | |
end | |
end | |
return @data.pop | |
end | |
def push(e) | |
@data.push(e) | |
i=@data.size-1 | |
while 0<i | |
t = (i-1)/2 | |
if @cp.(@data[i],@data[t]) | |
_swap(i,t) | |
i=t | |
else | |
break | |
end | |
end | |
return self | |
end | |
def shrink!(s) | |
return nil if @data.size<=s | |
@data.pop(@data.size-s) | |
end | |
def _swap(i,j) | |
@data[i],@data[j] = @data[j],@data[i] | |
end | |
end | |
10.times{ | |
h = Heap.new | |
10.times{h.push(rand(0..99))} | |
while (!h.empty?);printf "%3d",h.pop;end | |
puts "" | |
} | |
2000.times{ | |
h = Heap.new | |
100.times{h.push(rand(0..1000))} | |
l=h.pop | |
while (!h.empty?) | |
c=h.pop | |
if (l>c);puts "assert: #{l} > #{c}";exit;end | |
l=c | |
end | |
} | |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment