fork download
copy 
  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. string longestCommonPrefix(vector<string>& strs) {
  5.     string out = "";
  6.     if(strs.size() == 0 ){
  7.         return out;
  8.     }
  9.     //find the minimum length string since the longest common prefix can't be more than that length
  10.     string minLenStr = strs[0];
  11.     for(int i = 1; i < strs.size(); i++){
  12.         if(strs[i].length() < minLenStr.length()){
  13.             minLenStr = strs[i];
  14.         }
  15.     }
  16.     //loop over all string and match all the starting characters, update the maximum size possible based on the starting matching characters
  17.     int end = minLenStr.length();
  18.     for(int i = 0; i < strs.size(); i++){
  19.         int j = 0;
  20.         while(j < end){
  21.             if(minLenStr[j] != strs[i][j]){
  22.                 break;
  23.             }
  24.             j++;
  25.         }
  26.         //update the maximum possible size
  27.         if(j < end){
  28.             end = j;
  29.         }
  30.     }
  31.     return minLenStr.substr(0, end);
  32. }
  33.  
  34. int main() {
  35. 	vector<string> vec(4);
  36. 	vec[0] = "hello";
  37. 	vec[1] = "hello World";
  38. 	vec[2] = "hell";
  39. 	vec[3] = "helloween";
  40.  
  41. 	cout << longestCommonPrefix(vec) << endl;
  42. 	return 0;
  43. }
Success #stdin #stdout 0s 15240KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
hell
https://ideone.com/CWFcI8
language:
C++14 (gcc 8.3)
created:
6 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!