I have to find the sum of the absolute difference between consecutive elements of the array. But sumAbsArr function returns nun
var arr = [1, 5, 2];
var n = 3;
var cur = 0;
console.log(sumAbsArr(arr, n, cur))
function sumAbsArr(arr, n, cur) {
if (n == cur) {
return 0
}
var abs = Math.abs(arr[cur] - arr[cur + 1])
var ans = abs + sumAbsArr(arr, n, cur + 1)
return ans
}I think you are wrong at placing the condition. Look at arr[cur+1] (at line 11), when cur = 3 the cur+1 is out of range (arr index is start at 0 and end at arr.length-1 which is 2). So to prevent arr[cur+1] have NaN value, you have to change the condition
var arr = [1, 5, 2];
var n = 3;
var cur = 0;
console.log(sumAbsArr(arr, n, cur))
function sumAbsArr(arr, n, cur) {
// change the condition to stay within the range
if (cur == n-1) {
return 0
}
var abs = Math.abs(arr[cur] - arr[cur + 1])
var ans = abs + sumAbsArr(arr, n, cur+1)
return ans
}