ES6 Map to Array
function differentSymbolsNaive(str) {
// write code here.
const map = new Map();
const arr = Array.from(str);
for (const item of arr) {
if(!map.has(item)) {
map.set(item, item);
}
}
return [...map].length;
// return [...map.keys()].length;
}
Array.from
const map = new Map().set('a', 1).set('b', 2);
const array = Array.from(map, ([name, value]) => ({ name, value }));
console.log(array);
https://stackoverflow.com/questions/56795743/how-to-convert-map-to-array-of-object
https://stackoverflow.com/questions/35341696/how-to-convert-map-keys-to-array/35341828
https://stackoverflow.com/questions/8763125/get-array-of-objects-keys
refs
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