Longest Common Substring (task)

Question

Task:
Given multiple words, you need to find the longest string that is a substring of all words.

Input Format:
A string of words, separated by spaces. The string can also contain numbers.

Output Format:
A string, representing the longest common substring.
If there are multiple longest common substrings, output the smallest one in alphabetical order.

Sample Input:
SoloLearn Learning LearningIsFun Learnable

Sample Output:
Learn

My code failed in a task 4.
I can't find an error in a code. Help)
https://code.sololearn.com/cXd691C4aYTW/?ref=app

Answer 1

Jhon Doe
Try below.

text = input().split()

from itertools import permutations

words = set()
for i in range(0, len(text[0:])+2):
for j in permutations(text[0], i):
words.add(''.join(j))

substrings = []
for word in words:
count = 0
for i in text:
if word in i:
count += 1
if count == len(text):
substrings.append(word)

substrings.sort(key=len, reverse=True)

print(substrings[0])

Answer 2

https://www.sololearn.com/coach/95?ref=app

☝ url with the task

Answer 3

// Hello where. Here is My version on C#. it pass all 6 tests:
https://www.sololearn.com/ru/compiler-playground/c81zxq1Buzf4

using System;
using System.Collections.Generic;
using System.Linq;

public class Program
{
public static void Main()
{
string[] words = Console.ReadLine().Split(' ');
Array.Sort(words, (x, y) => x.Length.CompareTo(y.Length));
string word = words[0];
int length = word.Length;

for (int i = length; i > 0; i--)
{
HashSet<string> substrings = new HashSet<string>();
for (int j = 0; j <= length - i; j++)
{
substrings.Add(word.Substring(j, i));
}

List<string> ok = substrings.Where(ss => words.Skip(1).All(w => w.Contains(ss))).OrderBy(s => s).ToList();

if (ok.Any())
{
Console.WriteLine(ok[0]);
break;
}
}
}
}

Answer 4

It worked!

def main(word):
a=[]
for n in range(int(len(word)/2)+1):
for i in range(len(word)-1):
a.append(word[0:i+1])
a.append(word[i+1:])
a.append(word)
word=word[1:-1]
return a

c=[]

words=input().split()
for word in words:
c.append(set(main(word)))

result=sorted(set.intersection(*c), key=len, reverse=True)

print(result[0])