# A (beginner) problem with Cython, II

Why the following code generates a problem in Sage-Cython ?

(note the recursion and the global variable bb)

```
cpdef lintsolve(list T, list A, int m, int ep):
global bb;
cdef int t0,t,n,i,m1
cdef list A1,T1
if not A:
bb=[]
t0=T[0]
t=len(T)
if t==1 and m%t0==0:
A1=[ep]
A1.extend(A)
A1.append(m//t0)
bb.extend([A1])
if t>1:
n=m//t0
for i in range(n+1):
T1=T[1:]
m1=m-i*t0
A1=A[:]
A1.append(i)
lintsolve(T1,A1,m1,ep)
return bb
```

while the following code runs very well in Sage-Python :

```
def lintsolve(T,A,m,ep):
global bb;
if not A:
bb=[]
t0=T[0]
t=len(T)
if t==1 and m%t0==0:
A1=[ep]
A1.extend(A)
A1.append(m//t0)
bb.extend([A1])
if t>1:
n=m//t0
for i in range(n+1):
T1=T[1:]
m1=m-i*t0
A1=A[:]
A1.append(i)
lintsolve(T1,A1,m1,ep)
return bb
```