how does reduce work in javascript code example
Example 1: javascript reduce
var array = [36, 25, 6, 15];
array.reduce(function(accumulator, currentValue) {
return accumulator + currentValue;
}, 0);
Example 2: reduce javascript
const sum = array.reduce((accumulator, element) => {
return accumulator + element;
}, 0);
const product = array.reduce((accumulator, element) => {
return accumulator * element;
}, 1);
Example 3: reduce javascript
function reduce(array, func, seed) {
let previousResult;
if (seed === undefined) {
previousResult = array[0];
for (let i = 1; i < array.length; i++) {
previousResult = func(previousResult, array[i], i, array);
}
console.log(previousResult);
} else {
previousResult = seed;
each(array, function(e, i, a) {
previousResult = func(previousResult, e, i, array);
});
}
return previousResult;
};
Example 4: reduce javascript
const sum = array.reduce((accumulator, element[, idx[, sourceArray]]) => {
return accumulator + idx * 2 + element
}, 0);