JavaScript SUM SUM OBIEKTÓW
arr = [{x:1}, {x:3}]
arr.reduce((accumulator, current) => accumulator + current.x, 0);
Bhishma'S
arr = [{x:1}, {x:3}]
arr.reduce((accumulator, current) => accumulator + current.x, 0);
var accounts = [
{ name: 'James Brown', msgCount: 123 },
{ name: 'Stevie Wonder', msgCount: 22 },
{ name: 'Sly Stone', msgCount: 16 },
{ name: 'Otis Redding', msgCount: 300 } // Otis has the most messages
];
// get sum of msgCount prop across all objects in array
var msgTotal = accounts.reduce(function(prev, cur) {
return prev + cur.msgCount;
}, 0);
console.log('Total Messages:', msgTotal); // Total Messages: 461
const fruitTally = fruit.reduce((currentTally, currentFruit) => {
currentTally[currentFruit] = (currentTally[currentFruit] || 0) + 1
return currentTally
} , {})
// returns {"apple":3,"banana":3,"cherry":2,"mango":2,"apricot":1,"guava":2}