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part1 javascript higher order functions


  const companies=[
  {name:"facebook",start:"100",end:"110"}, {name:"amazon",start:"123",end:"321"},{name:"bamboo",start:"34",end:"45"}, {name:"netflix",start:"20",end:"223"}
]
const ages = [31,21,11,3,15,32,53,34,15,76,79,84,91]

//For each
companies.forEach((item)=>{console.log(item["name"] + "..elements")});

output:
facebook :elements
amazon :elements

// filter out ages that are below 21 (remove elements less than 21)

//filter
const canSmoke=ages.filter((age)=>(age>21))
console.log(canSmoke)
const oldestCompany = companies.filter((comp)=>{if (comp.end>100){return true;} })
//console.log("The oldest is: " + JSON.stringify(oldestCompany))
console.log("The oldest is: " + oldestCompany)
oldestCompany.forEach(x=>console.log(x))
const eightiesCompany = companies.filter(
company=> (company.start >=1980 && company.start <1990)
);

// sorting by company start date

const sortedCompanies = companies.sort(
(a,b)=> (a.start > b.start ? 1 : -1)
);
console.log(sortedCompanies)

o/p:-

[{"name":"netflix","start":20,"end":223},{"name":"bamboo","start":34,"end":45},{"name":"facebook","start":100,"end":110},{"name":"amazon","start":123,"end":321}] 

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