力扣 -- 376. 摆动序列

class Solution {
public:
    int wiggleMaxLength(vector<int>& nums) {
        int n=nums.size();
        vector<int> f(n,1);
        auto g=f;
        int ret=1;
        for(int i=0;i
        {
            for(int j=0;j
            {
                if(nums[j]>nums[i])
                {
                    f[i]=max(f[i],g[j]+1);
                }
                else if(nums[j]
                {
                    g[i]=max(g[i],f[j]+1);
                }
            }
            ret=max(f[i],g[i]);
        }
        return ret;
    }
};