Nested List Weight Sum

Given a nested list of integers, return the sum of all integers in the list weighted by their depth. Each element is either an integer, or a list -- whose elements may also be integers or other lists.

Example Given the list [[1,1],2,[1,1]], return 10. (four 1's at depth 2, one 2 at depth 1, 4 1 2 + 1 2 1 = 10) Given the list [1,[4,[6]]], return 27. (one 1 at depth 1, one 4 at depth 2, and one 6 at depth 3; 1 + 4 2 + 6 3 = 27)

Solution: DFS

    int dfs(int depth, const vector<NestedInteger> &nestedList) {
        int sum = 0;
        for (auto nestedInteger: nestedList) {
            if (nestedInteger.isInteger()) {
                sum += nestedInteger.getInteger() * depth;
            } else {
                sum += dfs(depth+1, nestedInteger.getList());
            }
        }
        return sum;
    }

    int depthSum(const vector<NestedInteger>& nestedList) {
        // Write your code here
        return dfs(1, nestedList);
    }