g1201_1300.s1247_minimum_swaps_to_make_strings_equal

Class Solution

java.lang.Object

g1201_1300.s1247_minimum_swaps_to_make_strings_equal.Solution

public class Solution
extends Object

1247 - Minimum Swaps to Make Strings Equal.

Medium

You are given two strings s1 and s2 of equal length consisting of letters "x" and "y" only. Your task is to make these two strings equal to each other. You can swap any two characters that belong to different strings, which means: swap s1[i] and s2[j].

Return the minimum number of swaps required to make s1 and s2 equal, or return -1 if it is impossible to do so.

Example 1:

Input: s1 = “xx”, s2 = “yy”

Output: 1

Explanation: Swap s1[0] and s2[1], s1 = “yx”, s2 = “yx”.

Example 2:

Input: s1 = “xy”, s2 = “yx”

Output: 2

Explanation:

Swap s1[0] and s2[0], s1 = “yy”, s2 = “xx”.

Swap s1[0] and s2[1], s1 = “xy”, s2 = “xy”.

Note that you cannot swap s1[0] and s1[1] to make s1 equal to “yx”, cause we can only swap chars in different strings.

Example 3:

Input: s1 = “xx”, s2 = “xy”

Output: -1

Constraints:

• 1 <= s1.length, s2.length <= 1000
• s1, s2 only contain 'x' or 'y'.

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
int	minimumSwap(String s1, String s2)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

minimumSwap

public int minimumSwap(String s1,
                       String s2)