findKthNumber是在当前范围内第k小的数。

 

class Solution {public:    double findMedianSortedArrays(vector
     
      & nums1, vector
      
       & nums2) {        int length1 = nums1.size();        int length2 = nums2.size();        int len = length1 + length2;        int mid = len/2;        if(len % 2 == 0)            return (findKthNumber(nums1,nums2,0,0,mid) + findKthNumber(nums1,nums2,0,0,mid+1))/2.0;        else            return findKthNumber(nums1,nums2,0,0,mid+1);    }            int findKthNumber(vector
       
         nums1,vector
        
          nums2,int start1,int start2,int k){        int length1 = nums1.size();        int length2 = nums2.size();        if(start1 >= length1)            return nums2[start2+k-1];        if(start2 >= length2)            return nums1[start1+k-1];        if(k == 1)            return min(nums1[start1],nums2[start2]);        int mid = k/2 - 1;        int num1 = start1 + mid >= length1 ? 0x7FFFFFFF : nums1[start1 + mid];        int num2 = start2 + mid >= length2 ? 0x7FFFFFFF : nums2[start2 + mid];        if(num1 > num2)            return findKthNumber(nums1,nums2,start1,start2 + mid + 1,k-k/2);        else            return findKthNumber(nums1,nums2,start1 + mid + 1,start2,k-k/2);            }    };
        
       
      
     

https://www.cnblogs.com/lupx/p/lupeixin.html