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.

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Yes

Example

Given the list[[1,1],2,[1,1]], return10. (four 1's at depth 2, one 2 at depth 1, 4 * 1 * 2 + 1 * 2 * 1 = 10)
Given the list[1,[4,[6]]], return27. (one 1 at depth 1, one 4 at depth 2, and one 6 at depth 3; 1 + 4_2 + 6_3 = 27)

/**
 * // This is the interface that allows for creating nested lists.
 * // You should not implement it, or speculate about its implementation
 * class NestedInteger {
 *   public:
 *     // Return true if this NestedInteger holds a single integer,
 *     // rather than a nested list.
 *     bool isInteger() const;
 *
 *     // Return the single integer that this NestedInteger holds,
 *     // if it holds a single integer
 *     // The result is undefined if this NestedInteger holds a nested list
 *     int getInteger() const;
 *
 *     // Return the nested list that this NestedInteger holds,
 *     // if it holds a nested list
 *     // The result is undefined if this NestedInteger holds a single integer
 *     const vector<NestedInteger> &getList() const;
 * };
 */
class Solution {
public:
    int depthSum(const vector<NestedInteger>& nestedList) {
        // Write your code here
        int depth = 1, sum = 0;
        queue<NestedInteger> q;
        for (const NestedInteger& item : nestedList) {
            q.push(item);
        }
        while (!q.empty()) {
            int size = q.size();
            for (int i = 0; i < size; ++i) {
                NestedInteger item = q.front(); q.pop();
                if (item.isInteger()) {
                    sum += item.getInteger() * depth;
                } else {
                    for (auto& it : item.getList()) {
                        q.push(it);
                    }
                }
            }
            ++depth;
        }

        return sum;
    }
};