sum of array using reduce javascript code example

Example 1: javascript sum of array

const sum = arr => arr.reduce((a, b) => a + b, 0);

Example 2: sum of all numbers in an array javascript

const arrSum = arr => arr.reduce((a,b) => a + b, 0)

Example 3: javascript reduce sum

arrSum = function(arr){  return arr.reduce(function(a,b){    return a + b  }, 0);}

Example 4: .reduce mdn

arr.reduce(callback( accumulator, currentValue[, index[, array]] )[, initialValue])