# Vishal Kumar
- Nodejs(~2), Typescript
- DynamoDB
- AWS - SQS, Lambda, Kinesis, S3
- Firebase, sendGrid, gupshup, newrelic, moengage, Google APIs

# Question 1:

const arrObj = [
    { age: 9, class: 6, name: 'A'},
    { age: 10, class: 5, name: 'B'}, 
    { age: 11, class: 6, name: 'C'},
    { age: 10, class: 5, name: 'D'},
    { age: 12, class: 6, name: 'E'},
    { age: 10, class: 5, name: 'F'},
    { age: 12, class: 7, name: 'G'},
]

const result = {
    5: { 
        10: ['B', 'D', 'F'], 
    },
    6: { 
        9: ['A']
        11: ['C'],
        12: ['E'],
    },
    7: { 
        12: ['G']
    }
}




function getResult(arrObj) {

    let result = {};

    arrObj.forEach(obj => {

        if (result[obj[clas]]) {
             reduceAgeAndName(result[obj[clas]], obj);

        } else {
            result[result[obj[clas]]] = {};
            reduceAgeAndName(result[result[obj[clas]]], obj);

        }
    });

}


function reduceAgeAndName(existing, newObj) {

    if (existing[newObj[age]].length) {

        existing[newObj[age]].push(newObj[name]);

    } else {
         existing[newObj[age]]  [newObj[name]]
    }

}

# Question 2:
- Array [1, 2, 3, 4, 5]
- length = 0 < length < Array.length

for(i = 0; i<arr.lenth-length)
let arr = new Array();

length = 3

i = 0, i++, i<arr.length-3
[1,2,3]
[2,3,4]
[3,4,5]

i= 1
i = i+2;

[1, 2, 3] =
[1, 2, 4]
[1, 2, 5]
[1, 3, 4]
[1, 3, 5]
[1, 4, 5]
[2, ...]

[1, 2, 3, 4, 5]

i= 0
getArray(arr,i, subArray);
getArrayWithMissedValue(arr,i+1, subArray)

i=0 [1] [] | i+1=1 [2] []

i= 1 [1,2]

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