A={
value:1,
items:[A,A,A] //itemsA
}is there any good way to find the sum of all the value in object A
A={
value:1,
items:[A,A,A] //itemsA
}is there any good way to find the sum of all the value in object A
function sum(arr) {
var _sum = 0;
arr.forEach(v => _sum += v);
return _sum;
}
function sumA(A) {
if(A.items && A.items.length) {
return sum([A.value].concat(a.items.map(sumA)));
} else {
return A.value;
}
} finally call sumA to sum. I wonder if this meets your requirements?
concat in sumA is for tail recursive optimization, but I'm not sure if you can do tail recursive optimization by writing this. A more understandable version:
function sumA(A) {
if(A.items && A.items.length) {
var sum = A.value;
for(let a of A.items) {
sum += sumA(a);
}
return sum;
} else {
return A.value;
}
}Previous: Yarn installation of jquery doubts?
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