Leetcode刷题笔记(c++)

排序

由于排序结果不需要返回，所以这里用temp1,2记录中间两个决定中位数即可

class Solution {
public:
    double findmid(vector<int>& nums){
        int n=nums.size();
        if(n%2==1)return (double)nums[n/2];
        else return ((double)nums[n/2-1]+(double)nums[n/2])/2;
    }
    double findMedianSortedArrays(vector<int>& nums1, vector<int>& nums2) {
        if(nums1.empty()&&nums2.empty())return 0.0;
        if(nums1.empty()) return findmid(nums2);
        if(nums2.empty()) return findmid(nums1);
        int n1=nums1.size();
        int n2=nums2.size();
        int temp1=0,temp2=0;
        int i=0,j=0,k=0;
        while(k<=(n1+n2)/2){
            temp1=temp2;
            k++;
            if(i<n1&&j<n2){
                if(nums1[i]<nums2[j]){
                    temp2=nums1[i];
                    i++;
                }else{
                    temp2=nums2[j];
                    j++;
                }
            }else if(i<n1){
                temp2=nums1[i];
                i++;
            }
            else{
                temp2=nums2[j];
                j++;
            }
        }
        if((n1+n2)%2==1)return temp2;
        return ((double)temp1+(double)temp2)/2;
    }
};

暴力解

class Solution {
public:
    double findmid(vector<int>& nums){
        int n=nums.size();
        if(n%2==1)return (double)nums[n/2];
        else return ((double)nums[n/2-1]+(double)nums[n/2])/2;
    }
    double findMedianSortedArrays(vector<int>& nums1, vector<int>& nums2) {
        if(nums1.empty()&&nums2.empty())return 0.0;
        if(nums1.empty()) return findmid(nums2);
        if(nums2.empty()) return findmid(nums1);
        int n=nums2.size();
        for(int i:nums2)nums1.emplace_back(i);
        sort(nums1.begin(),nums1.end());
        return findmid(nums1);
    }
};