1662. Check If Two String Arrays are Equivalent

Given two string arrays word1 and word2, return true if the two arrays represent the same string, and false otherwise.

A string is represented by an array if the array elements concatenated in order forms the string.

Example 1:

Input: word1 = ["ab", "c"], word2 = ["a", "bc"]
Output: true
Explanation:
word1 represents string "ab" + "c" -> "abc"
word2 represents string "a" + "bc" -> "abc"
The strings are the same, so return true.

Example 2:

Input: word1 = ["a", "cb"], word2 = ["ab", "c"]
Output: false

Example 3:

Input: word1  = ["abc", "d", "defg"], word2 = ["abcddefg"]
Output: true

Approach 1:

public class StringArrayEquivalent {
  public static void main(String[] args) {
    String[] word1 = {"ab", "c"};
    String[] word2 = {"a", "bc"};

    boolean answer = arrayStringsAreEqual(word1, word2);
    System.out.println("Both String arrays are equivalent: "+answer);
  }

  public static boolean arrayStringsAreEqual(String[] word1, String[] word2) 
  {
    StringBuilder sb1 = new StringBuilder();
    StringBuilder sb2 = new StringBuilder();

    for(String s:word1){
      sb1.append(s);
    }
    for(String s:word2){
      sb2.append(s);
    }
    if((sb1.toString().equals(sb2.toString()))){
      return true;
    }
    return false;
  }
}

output:

Both String arrays are equivalent: true

Step 1:

Initially, Create the new StringBuilder classes.

StringBuilder sb1 = new StringBuilder();

StringBuilder sb2 = new StringBuilder();

Step 2:

The string arrays can be converted to string.

convert the string array word1 into string by appending the each string to the StringBuilder class.

for(String s:word1){
    sb1.append(s);
}

Same for the word2 also.

Step 3:

Convert the StringBuilder to String using the toString() method.

We cannot directly compare the two StringBuilder objects because StringBuilder does not override the 'equals' method.

• By default, the 'equals' method in 'Object' class compare the references, not their content.

• To compare the content convert the StringBuilder to String using the toString() method.

step 4:

After converting to string check if both are equal return true else false.

My Solution Link: https://leetcode.com/problems/check-if-two-string-arrays-are-equivalent/submissions/1104840828/

Approach 2:

class Solution {
    public static void main(String[] args){
        String[] word1 = {"ab", "c"};
        String[] word2 = {"a", "bc"};

        boolean answer = arrayStringsAreEqual(word1, word2);
        System.out.println("Both String arrays are equivalent: "+answer);
    }
    public boolean arrayStringsAreEqual(String[] word1, String[] word2) {
        String s1 = String.join("",word1);
        String s2 = String.join("",word2);
        return s1.equals(s2);
    }
}

output:

Both String arrays are equivalent: true

Explanation:

Here join function is used to join the array without space.

String s1 = String.join("",word1);

word1 = [ "ab", "c" ]

after join() the output is "abc".

One more example:

String s1 = String.join("-",word1);

Here '-' it is the separator: "ab-c"

Then check the two strings are equals if equal return true else false.

My Solution Link: https://leetcode.com/problems/check-if-two-string-arrays-are-equivalent/submissions/1051495855/

Thank you for reading.

Happy coding :)