I am solving the mini-max task on hackerrank.
https://www.hackerrank.com/challenges/mini-max-sum/problem?isFullScreen=true
For that i have the following code where i use recursion until i hit the array length
let arr = [1,2,3,4,5];
let sumsArr = [];
function sumMiniMax(arr, length) {
let sum = 0;
for(let i = 0;i < arr.length;i++) {
if(i != length) {
sum += arr[i];
}
}
sumsArr.push(sum);
length = length + 1;
if(length == arr.length) {
let result = findMinAndMax(sumsArr);
console.log('result local', result);
return result
} else {
sumMiniMax(arr, length)
}
}
function findMinAndMax(sumsArr) {
return Math.min(...sumsArr) + '\n' + Math.max(...sumsArr)
}
let res = sumMiniMax(arr, 0);
console.log('res', res);
in the result local i am getting the expected output 10 and 14 but after the recursion is done i want to return the result from findMinAndMax to the original caller which is sumMiniMax
In that case i am getting only undefined but before i return the value we can see that the correct output in the local scope in found 10 and 14. Why is that ?
Not all of your code paths return a value. You need to propagate your result up the call stack. In your case the
return sumMiniMax(arr, length);
is missing in the else branch of your function sumMiniMax().
I think recursion in this case is kind of over-engineering. The task has a straightforward approach:
function miniMaxSum(arr) {
const sumWithout = (el) => {
const elIndex = arr.indexOf(el);
const arrWithout = arr.filter((_, i) => i !== elIndex);
return arrWithout.reduce((sum, num) => sum + num);
};
const maxEl = Math.max(...arr);
const minEl = Math.min(...arr);
console.log(sumWithout(maxEl), sumWithout(minEl));
};
miniMaxSum([1,2,3,4,5]);.as-console-wrapper{min-height: 100%!important; top: 0}You could take a single loop approach by having a sum of the three non min and non max values and keep min and max value for adding later.
function getMinMax(array) {
let min = array[0] < array[1] ? array[0] : array[1],
max = array[0] > array[1] ? array[0] : array[1],
sum = 0;
for (let i = 2; i < array.length; i++) {
const value = array[i];
if (min > value) {
sum += min;
min = value;
continue;
}
if (max < value) {
sum += max;
max = value;
continue;
}
sum += value;
}
return [min + sum, max + sum].join(' ');
}
console.log(getMinMax([1, 2, 3, 4, 5]));