I want to build a function that
For example, if I call this function with the input of [1,2,3,4], the output should be [1,3,6,10]. However, when I run my code, it returns an empty array.
The following is the code I got so far.
function sumOfArray(nums) {
var output = []; // tip: initialize like let output = [nums?.[0] ?? 0];
for(let i = 1 ; i < nums.length ; i++) {
nums[i] = nums[i] + nums[i-1];
output.push(nums[i]);
}
return output;
};
console.log(
'calling sumOfArray([1,2,3,4])',
sumOfArray([1,2,3,4])
);const input = [1,2,3,4]
const theFunctionYouWannaWrite = (acc, v) => {
acc.push(v + (acc[acc.length - 1] || 0))
return acc;
}
const output = input.reduce(theFunctionYouWannaWrite, [])
console.log(output)if you want to use it with for
const input = [1,2,3,4]
const theFunctionYouWannaWrite = (acc, v) => {
acc.push(v + (acc[acc.length - 1] || 0))
return acc;
}
function sumOfArray(nums) {
var output = [];
for(let i = 0 ; i < nums.length ; i++) {
theFunctionYouWannaWrite(output, nums[i])
}
return output;
};
console.log(sumOfArray(input))Just add first item in array initialization and everything works fine.
function sumOfArray(nums) {
var output = [nums[0]]; // tip: initialize like let output = [nums?.[0] ?? 0];
for(let i = 1 ; i < nums.length ; i++) {
nums[i] = nums[i] + nums[i-1];
output.push(nums[i]);
}
return output;
};
console.log(
'calling sumOfArray([1,2,3,4])',
sumOfArray([1,2,3,4])
);let
sum = 0,
nums = [1, 2, 3, 4],
res = [];
nums.forEach((item, index, arr) => {
sum += arr[index];
res.push(sum);
});
console.log(res);