# Z6-Rešenja

# file: 'z6-1.py'
import sys
from math import inf

class histogram:
def __init__(self, value, freq):
self.value = value
self.freq = freq

class node:
def __init__(self, freq):
self.freq = freq
self.left = None
self.right = None

def get_histogram(L):
d = []
res = []
for i in L:
if not i in d:
d.append(i)
for i in d:
a = histogram(i, L.count(i))
res.append(a)
return res

def get_min_freq_elem(H):
m = histogram('\0', inf)
for i in H:
if i.freq < m.freq:
m = i
return m

def remove_elem(el, L):
L.remove(el)

def put_elem(el, L):
L.append(el)

def make_new_elem(el1, el2):
n = node(el1.freq + el2.freq)
n.left = el1
n.right = el2
el1.par = n
el2.par = n
return n

def get_enc_val(ch, L):
res = ""
while not ch in L:
if ch.par.left == ch:
res += '0'
elif ch.par.right == ch:
res += '1'
ch = ch.par
return res[::-1]

def test(s):
print(s)
H = get_histogram(s)
C = H[:]
while len(H) > 1:
m1 = get_min_freq_elem(H)
remove_elem(m1, H)
m2 = get_min_freq_elem(H)
remove_elem(m2, H)
m = make_new_elem(m1, m2)
put_elem(m, H)
for ch in C:
print(ch.value, get_enc_val(ch, H))

if __name__ == "__main__":
test_cases = [['a', 'b'], ['a', 'b', 'a', 'b', 'a', 'b', 'a', 'b', 'a', 'b'], ['a', 'a', 'b', 'b', 'b', 'c', 'c', 'c', 'c'], ['a', 'a', 'b', 'b', 'b', 'c', 'c', 'c', 'c', 'd', 'd', 'd', 'd', 'd'], ['a', 'a', 'a', 'b', 'b', 'b', 'b', 'c', 'c', 'c', 'c', 'c', 'd', 'd', 'd', 'd', 'd', 'd', 'e', 'e', 'f']]
for s in test_cases:
test(s)