def my_abs(x):
if not isinstance(x, int) and not isinstance(x, float):
print('param type error.')
return None
if x >= 0:
return x
else:
return -x
print(my_abs(-55))
def sub_sum(L):
sum_ji=0
sum_ou=0
num=1
for x in L:
if num % 2 != 0:
sum_ji+=x
num+=1
else:
sum_ou+=x
num+=1
return sum_ji,sum_ou
print(sub_sum([1,3,2,4,3,5]))
