HTML&CSS&Javscript&Jquery
190819 reduce
猫猫
2019. 8. 23. 17:29
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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<script>
var a = [100,8,9,45,10,20];
var result = a.reduce(function(arr,j,k){
console.log("first para : ",arr, "second para: ",j,"third para: ",k);
//result
//first para : 7 second para: 8 third para: 1
//first para : 15 second para: 9 third para: 2
return arr-=j; //reduce는 처음을 기점으로 계속 마이너스 해나감.마치..토너먼트?
//1차원 배열->하나의 값(스칼라)
//2차원 배열->1차원배열로
});
console.log(result);
//result
//24
</script>
</head>
<body>
</body>
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