cloudsense

task_1-test.js

const findSumIndex = require('./task_1');
describe('findSumIndex', () => {
  it('should return -1 | Input [1,2,3]', () => {
    expect(findSumIndex([1,2,3])).toBe(-1);
  });
  
  it('should return 0 | Input [1]', () => {
    expect(findSumIndex([1])).toBe(0);
  });
  
  it('should return 2 | Input [1,2,3,2,1]', () => {
    expect(findSumIndex([1,2,3,2,1])).toBe(2);
  });
  
  it('should return 4 | Input [-6,4,3,5,7,3,1,2]', () => {
    expect(findSumIndex([-6,4,3,5,7,3,1,2])).toBe(4);
  });
});

task_1.js

function findSumIndex(input) {
    if (!input.length) return -1;
    let rightSum = input.reduce((acc, val) => acc + val, 0);
    let leftSum = 0;    
    
    for (let i = 0; i < input.length; i++) {  
        rightSum = rightSum - input[i];
        if (rightSum === leftSum) return i; 
        leftSum = leftSum + input[i];
    }
    
    return -1;
}

module.exports = findSumIndex;

task_3-test.js

const mostLeastFrq = require('./task_3');
describe('mostLeastFrq', () => {
  it('should return 21 | Input [1,2,2]', () => {
    expect(mostLeastFrq([1,2,2])).toBe(21);
  });
  
  it('should return 31 | Input [1,2,2,333]', () => {
    expect(mostLeastFrq([1,2,2,333])).toBe(31);
  });
  
  it('should return 24 | Input [11,222,3,3,4]', () => {
    expect(mostLeastFrq([11,222,3,3,4])).toBe(24);
  });
  
  it('should return 34 | Input [3,33224]', () => {
    expect(mostLeastFrq([3,33224])).toBe(34);
  });
  
});

task_3.js

function mostLeastFrq(input) {
    if (!input.length) return -1;
    let mf = 1, lf = 1, freq = 1;
    let arr = input.toString().replace(/\D/g, '').split('').map(Number).sort();
    let mfElem = arr[0], lfElem = arr[0];
    console.log(arr);
    for(let i=0; i < arr.length; i++){
        if(arr[i]===arr[i+1]){freq++;}
        else {freq=1;}
        if(freq>mf){mfElem = arr[i]; mf = freq;}
        if(freq<=lf && arr[i] != arr[i-1]){lfElem = arr[i]; lf = freq;}
    }
   return Number(mfElem + "" + lfElem);
}

module.exports = mostLeastFrq;