while True:
    try:
        str_1 = list(input())
        str_2 = list(input())
        len_1 = len(str_1)
        len_2 = len(str_2)
        a = []
        for i in range(len_1 + 1):
            b = []
            for j in range(len_2 + 1):
                b.append(i + j)
            a.append(b)
        for i in range(1,len_1 + 1):
            for j in range(1,len_2 + 1):
                if(str_1[i - 1] == str_2[j - 1]):
                    d = 0
                else:
                    d = 1
                a[i][j] = min(a[i - 1][j] + 1,a[i][j - 1] + 1,a[i-1][j-1] + d)
        print(a[len_1][len_2])
    except:
        break