Connection Status:
Competition Arena > NumberChanger
SRM 221 · 2004-12-01 · by AdminBrett · Brute Force
Class Name: NumberChanger
Return Type: int
Method Name: transform
Arg Types: (string, string)
Problem Statement

Problem Statement

You will be given 2 numbers start and finish each with the same number of digits. Both may have leading zeros. You are going to transform start into finish using the following kinds of transformation steps:
  • 1) Increment a digit less than 9 by 1. For example, changing 354 to 364.
  • 2) Decrement a digit greater than 0 by 1. For example, changing 354 to 254.
  • 3) Swapping two digits. For example, changing 354 to 453.
Return the fewest number of transformation steps required to change start into finish.

Constraints

  • start will contain between 1 and 8 characters inclusive.
  • Each character in start will be a digit ('0'-'9').
  • finish will contain the same number of characters as start.
Examples
0)
"01234567"
"01234567"
Returns: 0

No steps required.

1)
"11119999"
"99991111"
Returns: 4

4 swaps does the trick.

2)
"55555555"
"12345678"
Returns: 16

Swapping is of no use here.

3)
"77771111"
"00446688"
Returns: 16
4)
"00000000"
"99999999"
Returns: 72

Submissions are judged against all 99 archived test cases, of which 5 are shown here. Case numbers match the judge’s.

Coding Area

Language: C++17 · define a public class NumberChanger with a public method int transform(string start, string finish) · 99 test cases · 2 s / 256 MB per case

Submitting as anonymous