Longest Common Prefix

class Solution:
    def longestCommonPrefix(self, strs: List[str]) -> str:
        if not strs: return ""
        prefix = strs[0]
        for s in strs[1:]:
            while not s.startswith(prefix):
                prefix = prefix[:-1]
                if not prefix: return ""
        return prefix

class Solution {
public:
    string longestCommonPrefix(vector<string>& strs) {
        if (strs.empty()) return "";
        string prefix = strs[0];
        for (auto& s : strs) {
            while (s.find(prefix) != 0) {
                prefix = prefix.substr(0, prefix.size()-1);
                if (prefix.empty()) return "";
            }
        }
        return prefix;
    }
};

function longestCommonPrefix(strs: string[]): string {
    if (!strs.length) return "";
    let prefix = strs[0];
    for (const s of strs) {
        while (!s.startsWith(prefix)) {
            prefix = prefix.slice(0, -1);
            if (!prefix) return "";
        }
    }
    return prefix;
}