Problem:
Score : 200 points

Problem Statement

Given are two strings S and T.

Let us change some of the characters in S so that T will be a substring of S.

At least how many characters do we need to change?

Here, a substring is a consecutive subsequence. For example, xxx is a substring of yxxxy, but not a substring of xxyxx.

Constraints

The lengths of S and T are each at least 1 and at most 1000.

The length of T is at most that of S.

S and T consist of lowercase English letters.

Input

Input is given from Standard Input in the following format:

S
T

Output

Print the minimum number of characters in S that need to be changed.

Sample Input 1

cabacc
abc

Sample Output 1

1

For example, changing the fourth character a in S to c will match the second through fourth characters in S to T.

Since S itself does not have T as its substring, this number of changes - one - is the minimum needed.

Sample Input 2

codeforces
atcoder

Sample Output 2

6

Solution in Ruby (2.7.1) (judge verdict: Wrong Answer)

s = gets
t = gets

s_r = s.reverse
t_r = t.reverse

def ary_df(a,b)
  df = 0
  a.chars.each_with_index do |x, i|
    break unless b[i]
    if x != b[i]
      df += 1
    end
  end
  df
end
min = t_r.size
(1..s.size-1).each do |i|
  if t_r[0] == s_r[i]
    min_t = ary_df(t_r, s_r[i..-1])
    if min_t < min
      min = min_t
    end
  end
end

puts min