Why it's not working properly ??

Question

Given n, take the sum of the digits of n. If that value has more than one digit, continue reducing in this way until a single-digit number is produced. The input will be a non-negative integer.

Examples
16 --> 1 + 6 = 7
942 --> 9 + 4 + 2 = 15 --> 1 + 5 = 6
132189 --> 1 + 3 + 2 + 1 + 8 + 9 = 24 --> 2 + 4 = 6
493193 --> 4 + 9 + 3 + 1 + 9 + 3 = 29 --> 2 + 9 = 11 --> 1 + 1 = 2

My code:
a = input()
s = 0
while len(a) >1:
for j in a:
s = s+int(j)
a = str(s)
print(a)

Answer 1

Shahir one line is out of place. You need to move s = 0 inside the while loop.

Answer 2

If s does not get reset to 0 inside the while loop then it forever increments.

s=0
s=s+9+4+2=15
s=s+1+5=21
s=s+2+1=24
s=s+2+4=30...

Answer 3

👍👍

Answer 4

# Shahir try this
def sum(s):
t=0
for x in list(s): t+=int(x)
if t<10: return str(t)
else: return sum(str(t))

# Testing...

print(sum("16")) #7
print(sum("942")) #6
print(sum("132189")) #6
print(sum("493193")) #2
print(sum("6")) #6

# https://code.sololearn.com/cNEsbemtUy34/?ref=app

Answer 5

But what is wrong with my code