I can able to run in Intellij. the output is correct.
package com.codegym.task.task07.task0708;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
/*
Longest string
*/
public class Solution {
public static void main(String[] args) throws Exception {
//write your code here
ArrayList<String> list = new ArrayList<String>();
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
for(int i=0;i<5;i++){
list.add(reader.readLine());
}
for(int i=0;i<5;i++){
int length =list.get(i).length();
}
int num=0;
for(int i =0;i<list.size();i++)
{
if(num<list.get(i).length()) {
num=list.get(i).length();
}
}
for(int i=0;i<list.size();i++) {
if(num==list.get(i).length())
System.out.println(list.get(i));
}
}
}