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Lexicographically Smallest String After Applying Operations

Medium

You receive a string s of even length consisting of digits from 0 to 9 , and two integers a and b .

You can apply either of the following two operations any number of times and in any order on s:

  • Add a to all odd indices of s (0-indexed) . Digits post 9 are cycled back to 0 . For example, if s = "3456" and a = 5 , s becomes "3951" .

  • Rotate s to the right by b positions. For example, if s = "3456" and b = 1 , s becomes "6345" .

Produce the lexicographically smallest string you can obtain by applying the above operations any number of times on s .

A text a is lexicographically smaller than a string b (of the same length) if in the first position where a and b differ, string a has a letter that appears earlier in the alphabet than the corresponding letter in b . For example, "0158" is lexicographically smaller than "0190" because the first position they differ is at the third letter, and '5' comes before '9' .

Example 1

Input: s = "5525", a = 9, b = 2

Output: "2050"

Explanation: We can apply the following operations:

Start: "5525"

Rotate: "2555"

Add: "2454"

Add: "2353"

Rotate: "5323"

Add: "5222"

Add: "5121"

Rotate: "2151"

Add: "2050"

There is no way to obtain a string that is lexicographically smaller than "2050".

Example 2

Input: s = "74", a = 5, b = 1

Output: "24"

Explanation: We can apply the following operations:

Start: "74"

Rotate: "47"

Add: "42"

Rotate: "24"

There is no way to obtain a string that is lexicographically smaller than "24".

Example 3

Input: s = "0011", a = 4, b = 2

Output: "0011"

Explanation: There are no sequence of operations that will give us a lexicographically smaller string than "0011".

Constraints

  • 2 <= s.length <= 100
  • s.length is even.
  • s consists of digits from 0 to 9 only.
  • 1 <= a <= 9
  • 1 <= b <= s.length - 1

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