Problem
JavaScript function that takes in an array of Integers, arr, as the first and the only argument.
Our function should pick an index pair (i, j) such that (arr[i] + arr[j]) + (i - j) is maximum amongst all index pairs in the array. Our function should then return the maximum value.
For example, if the input to the function is −
const arr = [8, 1, 5, 2, 6];
Then the output should be −
const output = 11;
Output Explanation
Because if we choose i = 0 and j = 2 then the value will be −
(8 + 5) + (0 - 2) = 11
Which is indeed maximum for any index pair.
Example
The code for this will be −
const arr = [8, 1, 5, 2, 6];
const findMaximum = (arr = []) => {
let max = arr[0] + 0;
let res = -Infinity;
for(let i = 1; i < arr.length; i++){
res = Math.max(res, max + arr[i] - i);
max = Math.max(arr[i] + i, max);
};
return res;
};
console.log(findMaximum(arr));Output
And the output in the console will be −
11