Can you help me with a solution of hackerrank active traders problem?

Question

How can I rewrite this piece of code so that it works faster? Currently the execution time is more than 10 seconds.

def mostActive(customers):

    initial = sorted(list(set(customers)))
    filter_object = filter(lambda s: customers.count(s)/len(customers) >= 0.05, initial)
    return filter_object

if __name__ == '__main__':

    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    customers_count = int(input().strip())

    customers = []

    for _ in range(customers_count):
        customers_item = input()
        customers.append(customers_item)

    result = mostActive(customers)

    fptr.write('\n'.join(result))
    fptr.write('\n')

    fptr.close()

Answer 1

def mostActive(customers):
    store=dict()
    res=[]
    for i in customers:
        for i in store:
            store[i]+=1
        else:
            store[i]=1
            
    for i in store.items():
        if(i[1]/len(customers))*100>5 or (len(customers)*5)/100>=5:
            if(1[1]/len(customers))*100 >=(len(customers)*5)/100>=5 or (1[1]/len(customers))*100>=5:
                res.append(i[0])
    return sorted (res)

Answer 2

   public static List<string> mostActive(List<string> customers)
    {
        List<string> res = new List<string>();
        foreach (var c in customers)
        {
            double count = customers.Count(a => a.Contains(c));
            double per = (count / customers.Count()) * 100;
            if (!res.Contains(c) && per>=5)
            {
                res.Add(c);
            }
        }
        return res.OrderBy(r=>r).ToList();
    }

Answer 3

A Java 7 solution (without lambdas)

public static List<String> mostActive(List<String> customers) {
    int size = customers.size();

    Map<String, Integer> map = new HashMap<>();
    for (String customer : customers) {
        if (map.containsKey(customer)) {
            map.put(customer, map.get(customer) + 1);
        } else {
            map.put(customer, 1);
        }
    }

    List<String> result = new ArrayList<>();
    for (String key : map.keySet()) {
        double currentCustomerPercent = (double) (map.get(key)) / (double) size;

        if (currentCustomerPercent * 100 >= 5.0) {
            result.add(key);
        }
    }
    Collections.sort(result);
    return result;
}

Answer 4

def mostActive(customers):

n=len(customers)
res=dict()
for i in customers:
    if i not in res:
        res[i]=1
    else:
        res[i]+=1
perc=dict()
for i in res:
    perc[i]= (res[i]/n)*100
b=[]
for i in perc:
    if perc[i]>=5:
        b.append(i)
return(sorted(b))