1662. Check If Two String Arrays are Equivalent.md

1662. Check If Two String Arrays are Equivalent

---

the first one in Weekly Contest 216.

leetcode Daily Challenge on January 8th, 2021.

---

Difficulty : Easy

Related Topics : String

---

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

Constraints:

• 1 <= word1.length, word2.length <= 10^3
• 1 <= word1[i].length, word2[i].length <= 10^3
• 1 <= sum(word1[i].length), sum(word2[i].length) <= 10^3
• word1[i] and word2[i] consist of lowercase letters.

---

Solution

• mine
  • Java
    • Runtime: 0 ms, faster than 100.00%, Memory Usage: 37.1 MB, less than 80.83% of Java online submissions

      // O(N)time
      // O(N)space
      public boolean arrayStringsAreEqual(String[] word1, String[] word2) {
          StringBuilder w1 = new StringBuilder();
          StringBuilder w2 = new StringBuilder();
          for(String w : word1){
              w1.append(w);
          }
          for(String w : word2){
              w2.append(w);
          }
          if(w1.length() != w2.length()) return false;
          return w1.toString().equals(w2.toString());
      }
      

---