2483. Minimum Penalty for a Shop

class Solution {
public:
    int bestClosingTime(string customers) 
    {
        int penalty = 0;
        for(int i=0; i<customers.length(); i++)
        {
            if(customers[i]=='Y')
                penalty++;
        }

        if(penalty==0)  return 0;

        int min = penalty;
        int ans = 0;

        for(int i=0; i<customers.length(); i++)
        {
            if(customers[i]=='Y')
                penalty--;
            else
                penalty++;

            if(penalty<min)
            {
                min = penalty;
                ans = i+1;
            }
        }
        return ans;
    }
};