leetcode

3043.cpp (574B)

 class Solution {
   public:
     int longestCommonPrefix(const vector<int> &arr1, const vector<int> &arr2) const {
         unordered_set<int> us;
         int res = 0;
 
         for (int n : arr1) {
             while (n > 0) {
                 us.insert(n);
                 n /= 10;
             }
         }
 
         for (int n : arr2) {
             while (n > 0) {
                 if (us.count(n)) {
                     res = max(res, (int)log10(n) + 1);
                     break;
                 }
                 n /= 10;
             }
         }
 
         return res;
     }
 };