14. Longest Common Prefix - Easy

Write a function to find the longest common prefix string amongst an array of strings.

If there is no common prefix, return an empty string "".

Example:
Input: strs = ["flower","flow","flight"]

Output: "fl"

Constraints:

  • 1 <= strs.length <= 200
  • 0 <= strs[i].length <= 200
  • strs[i] consists of only lowercase English letters if it is non-empty

Solution:

var longestCommonPrefix = function(strs) {

    let res = '';

    let prefix = strs[0];

    for (let i = 0; i < prefix.length; i++) {

            if (strs.some(str => str[i] !== prefix[i])) {

                break;
              }

            res += prefix[i];

        }

    return res;

}


Thoughts:
This was a difficult one and I gave up after 30 minutes. The solution above is easy enough to understand. I have solved quite a few problems today so I am tired now and need to stop as I'm not practising as well as I should be. I'd give this a 4/10 for confidence. Should be a medium IMO. I'll come back to it at some point.

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