题解 | #在两个长度相等的排序数组中找到上中位数#

class Solution {
public:
/**
* find median in two sorted array
* @param arr1 int整型vector the array1
* @param arr2 int整型vector the array2
* @return int整型
*/
int findMedianinTwoSortedAray(vector<int>& arr1, vector<int>& arr2) {
// write code here
if(arr1.size() == 1) return min(arr1[0],arr2[0]);///特判
int n = arr1.size();///数组长度
int l1 = 0,r1 = n -1 ,l2 = 0,r2 = n -1;///初始指针
///元素个数位奇数，flag = 1，为偶数flag =0
int flag = ((r1 - l1 + 1) & 1);
while(l1 < r1){</int></int>

        int mid1 = l1 + ((r1 - l1) >> 1);
        int mid2 = l2 + ((r2 - l2) >> 1);
        ///更新区域的个数，奇数，flag = 1，为偶数flag =0
        flag = ((r1 - l1 + 1) & 1);
        ///若两数组中位数相等，整体的中位数也是这个
        if(arr1[mid1] == arr2[mid2]) return arr1[mid1];
        else if(arr1[mid1] > arr2[mid2]){
            ///如果区域个数是奇数
            if(flag){
                r1 = mid1;
                l2 = mid2;
            }else{
            ///如果区域个数是偶数
                r1 = mid1;
                l2 = mid2 + 1;
            }

        }else{
            ///如果区域个数是奇数
            if(flag){
                l1 = mid1;
                r2 = mid2;

            }else{
                ///如果区域个数是偶数
                l1 = mid1 + 1;
                r2 = mid2;
            }
        }

    }

    return min(arr1[l1],arr2[l2]);

}

};