# Question 1: DS Algo Problem

Find the max sum on an array.
- pick any number(ith index), cannot pick i-1th index and i+1th index

[1, 2, 3, 4, 5]- (1, 3, 5) = 9
[1, 2,-3, 4, 5]- (2, 5) = 7
[7, 8, 2] - (7, 2) = 9

[2,5,8,3,6,9,7] - (3,5,9) = 17 , (8,2,6,7) = 23
[1,2,3,4,5,6,7,8] -
[10, 1, 1, 10] = (10, 10) = 20

Sort the array and store in a new var
take the 1st elem in outputArr
add the 2nd elem if its not a neighbour of any previous elem
also so on till the last elem

this will run for 2 times
one will start from elem at pos 0
second will start from elem at pos 1. for output1 and output2

get sum of the outputs without including negative integers.
return which is maximum output1 or output2

# Question 2: Db Design

User service. (user table)
Chat service.
- one to chat. listing of conversations. group chat.

one to one:
{
chatBetween: {
uuid1:
uuid2:
}
conversation: [
{
createdAt:
From:
content: // can be text or url,

},
updatedAt:
]
}
...........................................

listingConvo:
{
uuid:
chatWith: // can be uuid or groupId
}
.............................................

group chat:
{
groupId:
chatBetween: [U1, U2,...Un],
conversation: [
{
createdAt:
From: uuid,
content: // can be text or url,
},
previousUsers: [U7, U12,,, Un],
updatedAt:

}