[Algorithm] 46 week(12.12 ~ 12.17) 2/3

77. Combinations

/**
 * @param {number} n
 * @param {number} k
 * @return {number[][]}
 */
var combine = function(n, k) {
    const result = [];

    const dfs = (array, start, end) => {
        if(end === 0) {
            result.push([...array]);
        }

        for(let i = start; i < n + 1; i++){
            array.push(i);
            dfs(array, i + 1, end - 1);
            array.pop();
        }
    }

    dfs([], 1, k);

    return result;
};