565. Array Nesting

简单题，本来还想用dfs搜素，后来发现根本不需要，直接处理即可

class Solution {
public:

    int findCircle(int start, vector<int>& nums, vector<int>& visit)
    {
        int temp=start;
        int count=1;
        while(start!=nums[temp]){
            temp=nums[temp];
            visit[temp]=1;
            count++;
        }

        return count;
    }



    int arrayNesting(vector<int>& nums) {

        int maxCircle=0;
        vector<int> visit(nums.size(),0);
        for(int i=0;i<nums.size();i++)
        {
            if(visit[i]==0){
                visit[i]=1;  
                int circle = findCircle(i,nums,visit);
                maxCircle = maxCircle>circle?maxCircle:circle;
            }
        }

        return maxCircle;
    }
};