The function should find all possible combinations of m numbers that add up to a number n,given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers.
For example − If the inputs are −
const m = 3, n = 4;
Then the output should be −
const output = [ [1, 2, 4] ];
If the inputs are −
const m = 3, n = 9;
Then the output should be −
const output = [ [1, 2, 6], [1, 3, 5], ];
Example
The code for this will be −
const m = 3, n = 9; const findSum = (m, n) => { const search = (from, prefix, m, n) => { if (m === 0 && n === 0) return res.push(prefix); if (from > 9) return; search(from + 1, prefix.concat(from), m − 1, n − from); search(from + 1, prefix, m, n); }; const res = []; search(1, [], m, n); return res; }; console.log(findSum(m, n));
Output
And the output in the console will be −
[ [ 1, 2, 6 ], [ 1, 3, 5 ], [ 2, 3, 4 ] ]