Python Project: Havel-Hakimi Algorithm

 Hey guys, this project in on Havel-Hakimi theorem. I have written a simple program to check whether a given degree sequence is graphical or not. Here's the code:

# First we take the length of the initial sequence

n = int(input("Enter length of the sequence: "))

# Next we enter the elements of the sequence

print("Enter the sequence d_n: ")

d = []

for i in range(n):

v = int(input())

d.append(v)

# next we run a loop, which is basically the algorithm.

while True:

d.sort(reverse=True)

m = d[0]

if m==0 and d[len(d)-1] == 0:

print("The sequence is graphical.")

break

elif m>len(d)-1:

print("The sequence is not graphical")

else:

for x in d:

if x<0:

print("The sequence is not graphical.")

break

d.pop(0)

for i in range(m):

d[i] = d[i]-1

print(d)