python下大数相加

s1=input('please enter number:')
s2=input('please enter number:')
L1=[0]
L2=[0]
for i in range(0,len(s1)):
	L1.append(int(s1[i]))
for i in range(0,len(s2)):
	L2.append(int(s2[i]))
if(len(s1)>len(s2)):
 for i in range(len(s1)-len(s2)):
    L2.append(0)
elif(len(s1)<=len(s2)):
	for i in range(len(s2)-len(s1)):
		L1.append(0)
for i in range(len(L1)):
        L1[i]=L1[i]+L2[i]
A=B=len(L1)-1
while A>0:
 	if((L1[A])/10)>=1:  # or if((L1[A]//10)>0)
 		L1[A]=L1[A]%10
 		L1[A-1]=L1[A-1]+1
 	A-=1
if L1[0]==0:
        for i in range(1,B+1):
                print(L1[i],end='')
elif L1[0]!=0:
        for i in range(B+1):
                print(L1[i],end='')