I came across the problem **Breadth First Search: Shortest Reach** in Hackerrank and here was my solution in **python**. However my code only passed one Test Cases among the 7. Where am I wrong in this implementation ?

```
#Hackerrank
#Topic : Graphs
#Url : https://www.hackerrank.com/challenges/bfsshortreach/problem
def bfs(i, n, E):
level = [-1] * (n+1)
queue = []
level[i] = 0
queue.append(i)
while len(queue) > 0:
head = queue[0]
queue = queue[1:]
for j,k in E:
if j == head:
if level[k] == -1:
level[k] = 1 + level[j]
queue.append(k)
return level
q = int(input())
for case in range(q):
e = input().split(" ")
n = int(e[0])
m = int(e[1])
E = []
for edge in range(m):
e = input().split(" ")
u = int(e[0])
v = int(e[1])
E.append([u,v])
s = int(input())
distance = bfs(s, n, E)
dist = []
for i in distance[1:]:
if i > 0:
dist.append(str(i*6))
if i < 0:
dist.append(str(-1))
print(" ".join(dist))
#print("")
```