reduce(), reduceRight()

reduce()

배열 요소 하나로 정리 : 반환(결괏값)

{
    const arrNum1 = [100, 200, 300, 400, 500];
    const arrReduce1 = arrNum1.reduce(element => element)
    //결과값 : 100

    const arrNum2 = [100, 200, 300, 400, 500];
    const arrReduce2 = arrNum2.reduce((previous, current) => previous + current)
    //결과값 : 1500

    const arrNum3 = [100, 200, 300, 400, 500];
    let sum=0;
    for (let i=0; i<arrNum3.length; i++){
        sum = sum + arrNum3[i]
        //결과값 : 1500

    const arrNum4 =[[100,200],[300,400]];
    const arrReduce4 = arrNum4.reduce((p,c) => p.concat(c));
    //결과값 : 100,200,300,400
}

reduceRight()

배열 요소 하나로 정리 : 반환(결괏값)

{
    const arrNum5 = ["javascript", "react", "vue"]
    const arrReduce5 = arrNum5.reduceRight((p,c) => p+c);
    //결과값 : vuereactjavascript
}