Python in huffman coding error when the number of digits are more than 10

Question

import heapq

f = [int(x) for x in input().split()]

T=[]

for i in range(len(f)):
    heapq.heappush(T,(f[i],str(i)))

while len(T)>1:
    a=heapq.heappop(T)
    b=heapq.heappop(T)
    heapq.heappush(T,(a[0]+b[0],'('+a[1]+' '+b[1]+')' ))

temp = 0
cost = 0
index= 0
for i in T[0][1]:
    if i == "(":
        temp = temp + 1
    elif i == ")":
        temp = temp - 1
    elif i == " ":
        continue
    else:
        cost = cost + (temp*f[int(i)])
        if i != "(" or ")" or " ":
            index*=10
            index+f[int(i)]


print(cost)

I am trying to make Huffman coding prefix-free cost code. my code works well, but when inputs are more than 9, it makes an error. I found when f[int(i)] is more than 10, it makes an error because the code reads it as 1 and 0. how can I fix this error?

> 43 13 12 16 9 7
230#correct
> 13 5 11 7 15 1 14 20 10 12 9
425#wrong

Answer 1

Update

the cost can be calculate while building the huffman tree.

import heapq

f = [int(x) for x in input().split()]

T=[]

for i in range(len(f)):
    heapq.heappush(T,(f[i],0,str(i)))

while len(T)>1:
    a=heapq.heappop(T)
    b=heapq.heappop(T)
    heapq.heappush(T,(a[0]+b[0],a[0]+b[0]+a[1]+b[1],'('+a[2]+' '+b[2]+')' ))

cost=heapq.heappop(T)[1]
print(cost)

---

Think "i" walk to the arrow, int(i) is 1, but the expect value is 10.

[(117, '(((2 9) (((5 1) 3) 0)) ((6 4) ((10 8) 7)))')]
                                        ^

You can check the code, it store the index value and caculate the cost after the walk through the full index string.

import heapq

f = [int(x) for x in input().split()]

T=[]

for i in range(len(f)):
    heapq.heappush(T,(f[i],str(i)))

while len(T)>1:
    a=heapq.heappop(T)
    b=heapq.heappop(T)
    heapq.heappush(T,(a[0]+b[0],'('+a[1]+' '+b[1]+')' ))

temp = 0
cost = 0
index= -1
for i in T[0][1]:
    if i == "(":
        temp = temp + 1
    elif i == ")":
        if index != -1:
            cost = cost + (temp*f[index])
            index = -1
        temp = temp - 1
    elif i == " ":
        if index != -1:
            cost = cost + (temp*f[index])
            index = -1
    else:
        if index == -1:
            index = int(i)
        else:
            index = 10 * index + int(i)

print(cost)