Syntax error Program to find minimum swaps required to make given anagram in python

Program to find minimum swaps required to make given anagram in python

Suppose we have two strings S and T and they are anagrams of each other. We have to find the minimum number of swaps required in S to make it same as T.

So, if the input is like S = "kolkata" T = "katloka", then the output will be 3, as can swap in this sequence [katloka (given), kotlaka, koltaka, kolkata].

To solve this, we will follow these steps −

  • Define a function util() . This will take S, T, i
  • if i >= size of S , then
    • return 0
  • if S[i] is same as T[i], then
    • return util(S, T, i + 1)
  • x := T[i]
  • ret := 99999
  • for j in range i + 1 to size of T, do
    • if x is same as S[j], then
      • swap S[i] and S[j]
      • ret := minimum of ret and (1 + util(S, T, i + 1))
      • swap S[i] and S[j]
  • return ret
  • From the main method do the following:
  • return util(S, T, 0)

Let us see the following implementation to get better understanding −

Example 

Live Demo

class Solution:
   def util(self, S, T, i) :
      S = list(S)
      T = list(T)
      if i >= len(S):
         return 0
      if S[i] == T[i]:
         return self.util(S, T, i + 1)
      x = T[i]
      ret = 99999;
      for j in range(i + 1, len(T)):
         if x == S[j]:
            S[i], S[j] = S[j], S[i]
            ret = min(ret, 1 + self.util(S, T, i + 1))
            S[i], S[j] = S[j], S[i]
      return ret
     
   def solve(self, S, T):
      return self.util(S, T, 0)

ob = Solution()
S = "kolkata"
T = "katloka"
print(ob.solve(S, T))

Input

"kolkata", "katloka"

Output

3
Updated on: 2020-12-02T05:33:15+05:30

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