Notes

Q.1 Given a string, find the substring based on following conditions,

The substring must be the longest one of all the possible substring in the given string.
There must not be any repeating characters in the substring.
If there is more than one substring satisfying the above two conditions, then print the substring which occurs first.
Length of the substring must be minimum 3.
If there is no substring satisfying all the aforementioned conditions then print -1.


Q.2
Given an array of integers, find the combination of integers forming a sequence which satisfies the below conditions:

The ith integer must satisfy the given equation in the sequence

2. The length of the sequence must be maximum possible

3. If there is more than one sequence satisfying above two conditions then print that sequence which contains least integers.
In case there is no combination of integers possible then print -1.
See the example below:

Example 1:
If the given integers are 4, 2, 7, 5, 3, 8, 10, 11, 19 then the possible combinations of integers satisfying above conditions are 2, 3, 5, 8 and 3, 8, 11, 19 and hence the output must be 2, 3, 5, 8. Here you cannot form any other combination of integers whose length is greater than 4 and satisfies the given equation.
Example 2:
If the given integers are 1,5,6,10 then print -1.