寻找两个正序数组的中位数

class Solution {
public:
    double findMedianSortedArrays(vector<int>& nums1, vector<int>& nums2) {
        int len1 = nums1.size();
        int len2 = nums2.size();
        
        int mid = (len1 + len2) / 2;
        bool odd = (len1 + len2) % 2 != 0;//奇数
        mid = odd ? mid++ : mid;
        if (len1 == 0 || len2 == 0) {
            vector<int>& nums = len1 == 0 ? nums2 : nums1;
            return odd? nums[mid]: (nums[mid-1]+(nums[mid]))/2.0 ;
        }

        int i1 = 0;
        int i2 = 0;
        int last = nums1[i1] <= nums2[i2]? nums1[i1]: nums2[i2];
        // 1 3 5 7 9 10; 2 4 6 8
        for (;;) {            
           
            //移动
            //vector<int>* pTarget = nullptr;
            if (nums1[i1] < nums2[i2]) {
                last = nums1[i1++];
            }
            else {
                last = nums2[i2++];
            }

            if ((i1 == len1) || (i2 == len2)) {
                vector<int>* pTarget = nullptr;
                int index;
                if (i1 == len1) {
                    pTarget = &nums2;
                    index = mid - (i1);
                }
                else {
                    pTarget = &nums1;
                    index = mid - (i2);
                }
                last = (index == 0 || last > (*pTarget)[index - 1]) ? last : (*pTarget)[index - 1];
                return odd ? (*pTarget)[index] : (last + (*pTarget)[index]) / 2.0;
            }

            //终结
            if (i1+i2 == mid) {
                int cur = nums1[i1] < nums2[i2] ? nums1[i1] : nums2[i2];
                if (odd) {
                    return cur;
                }
                else {
                    return (last + cur) / 2.0;
                }
            }
        }
        return 0.0;
    }
};

提交代码

代码有点难懂。效率还好。