while True:
try:
s1=input()
s2=input()
l1=len(s1)+1
l2=len(s2)+1
edit=[[i+j for j in range(l2)] for i in range(l1)]#得到一个edit表
for i in range(1,l1):
for j in range(1,l2):
if s1[i-1]==s2[j-1]:
d=0
else:
d=1
edit[i][j]=min(edit[i][j-1]+1,edit[i-1][j]+1,edit[i-1][j-1]+d)
print(edit[-1][-1])
except:
break