Zigzag Iterator

描述

TODO

分析

细节实现题。

代码

Java

// Zigzag Iterator
public class ZigzagIterator {
    private Iterator<Integer> i, j, tmp;

    public ZigzagIterator(List<Integer> v1, List<Integer> v2) {
        j = v1.iterator();
        i = v2.iterator();
    }

    public int next() {
        if (j.hasNext()) { tmp = j; j = i; i = tmp; }
        return i.next();
    }

    public boolean hasNext() {
        return i.hasNext() || j.hasNext();
    }
}

C++

// Zigzag Iterator
class ZigzagIterator {
public:
    ZigzagIterator(vector<int>& v1, vector<int>& v2) {
        j = v1.cbegin(), j_end = v1.cend();
        i = v2.cbegin(), i_end = v2.cend();
    }

    int next() {
        if (j != j_end) {std::swap(i, j); std::swap(i_end, j_end);}
        return *i++;
    }

    bool hasNext() {
        return i != i_end || j != j_end;
    }
private:
    vector<int>::const_iterator i, j, i_end, j_end;
};