643. Maximum Average Subarray I

static int wing=[]()
{
    std::ios::sync_with_stdio(false);
    cin.tie(NULL);
    return 0;
}();

class Solution 
{
public:
    double findMaxAverage(vector<int>& nums, int k) 
    {
        int sz=nums.size();
        double maxsum=0.0;
        double cursum=0.0;
        for(int i=0;i<k;i++)
            cursum+=nums[i];
        maxsum=cursum;
        for(int j=k;j<sz;j++)
        {
            cursum=cursum-nums[j-k]+nums[j];
            maxsum=max(cursum,maxsum);
        }
        return maxsum/k;
    }
};

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