题目:
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题解:
cpp
class NestedIterator {
private:
vector<int> vals;
vector<int>::iterator cur;
void dfs(const vector<NestedInteger> &nestedList) {
for (auto &nest : nestedList) {
if (nest.isInteger()) {
vals.push_back(nest.getInteger());
} else {
dfs(nest.getList());
}
}
}
public:
NestedIterator(vector<NestedInteger> &nestedList) {
dfs(nestedList);
cur = vals.begin();
}
int next() {
return *cur++;
}
bool hasNext() {
return cur != vals.end();
}
};