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  1. Prepare
  2. Data Structures
  3. Stacks
  4. Waiter
  5. Discussions

Waiter

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364 Discussions

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  • manceraaxel
     + 0 comments

    def generate_sieve(): constraint = pow(10, 4) boolean_sieve = [True] * (constraint + 1) boolean_sieve[0] = boolean_sieve[1] = False sieve = []

    for i in range(len(boolean_sieve))[2:]:
    if boolean_sieve[i]:            
        for j in range(len(boolean_sieve))[i*2::i]:
            boolean_sieve[j] = False            

    if i * i >= constraint:
        break

for i in range(len(boolean_sieve)):
    if boolean_sieve[i]:
        sieve.append(i)

return sieve

    def waiter(number, q): answers = [] sieve = generate_sieve() A = number

    for i in range(q):
    next_A = []
    B = []

    while A:
        plate = A.pop()          
        if plate % sieve[i] == 0:
            B.insert(0, plate)       
        else:
            next_A.append(plate)

    answers.extend(B)
    A = next_A

answers.extend(reversed(A))

return answers

  • anastasiya_kala1
     + 0 comments

    Java solution with sieve of eratosthenes for primes

    public static List<Integer> waiter(List<Integer> number, int q) {
        Stack <Integer> supportStack = new Stack<>();
        List<Integer> result = new ArrayList<>();
        int max = getMax(number);
        List<Integer> primes = getPrimes(max, number.size());
       
        for (int i = 0; i < q; i++) {
            int prime = primes.get(i);
            for (Integer n : number) {
                if (n % prime == 0) {
                    result.add(n);
                } else {
                    supportStack.push(n);
                }
            }
            number.clear();
            while (!supportStack.isEmpty()) {
                number.add(supportStack.pop());
            }
        }
        for (int i = number.size() - 1; i >= 0; i--) {
            result.add(number.get(i));
        }       
        return result;
    }
    
    private static int getMax(List<Integer> number) {
        int max = 0;
        for (Integer i : number) {
            if (i > max) {
                max = i;
            }
        }
        return max;
    }
    
    private static List<Integer> getPrimes (int n, int cap) {
        List<Integer> primes = new ArrayList<Integer>();
        boolean[] prime = new boolean[n + 1];
        for (int i = 0; i <= n; i++) {
            prime[i] = true;
        }

        for (int p = 2; p * p <= n; p++) {
            if (prime[p]) {
                for (int i = p * p; i <= n; i += p)
                    prime[i] = false;
            }
        }

        for (int i = 2; i <= n; i++) {
            if (prime[i] && primes.size() < cap)
                primes.add(i);
        }
        return primes;        
    }

  • chayanraicse2025
     + 0 comments
    bool isprime(int n)
{
    for(int i=2;i<(n/2)+1;i++)
    {
        if(n%i == 0)
        {
            return false;
        }
    }
    return true;
}
vector<int> waiter(vector<int> number, int q) 
{
    vector<int> p,a,b,res;
    vector<int> temp;
    int x;
    for(int i=2;i<10000;i++)
    {
        if(isprime(i))
        {
            p.push_back(i);
        }
    }    
    
    for(int i=0;i<q;i++)
    {
        int size = number.size();
        for(int j=0;j<size;j++)
        {
            x = number.back();
            
            if(x%p[i] == 0)
            {
                b.push_back(x);
                number.pop_back();
            }
            else
            {
                a.push_back(x);
                number.pop_back();
            }
        }
        number = a;
        a.clear();
        while(!b.empty())
        {
            res.push_back(b.back());
            b.pop_back();
        } 
    }
    while(!number.empty())
    {
        res.push_back(number.back());
        number.pop_back();
    }
    return res;
}

  • dibyajyotiparid1
     + 0 comments

    java solution

    class Result {

    /*
 * Complete the 'waiter' function below.
 *
 * The function is expected to return an INTEGER_ARRAY.
 * The function accepts following parameters:
 *  1. INTEGER_ARRAY number
 *  2. INTEGER q
 */
 public static boolean isprime(int n ) {
     for (int i = 2 ; i <= n+2 ; i++) {
         if ( i!=n && n%i==0) {
             return false;
         }
     }
     return true;
 }

    public static List waiter(List number, int q) { // Write your code here

           Stack <Integer> sc = new Stack<>();
       Stack <Integer> scB = new Stack<>();
       List<Integer> ans = new ArrayList<>();
       int prime = 1 ;

   //for prime  
   for (int i = 1 ; i <= q ; i++ ) {
      prime++;
      while (!isprime(prime)) {
          prime++;
      } 
      //process 
       if (i == 1 ) { 
           for (int k = number.size()-1; k>=0 ; k--) {
               if (number.get(k) % prime == 0) {
                   scB.push(number.get(k));
                    //System.out.println(scB.peek() +"  " + i+ "scb");
               } else {
                   sc.push(number.get(k));
                   // System.out.println(sc.peek() +"  " + i+ "sc");
               }
           }

       } else {
            Stack <Integer> scA1 = new Stack<>();
              while ( !sc.empty()){ 
                if (sc.peek()% prime ==0) {
                   scB.add(sc.pop());
                   //System.out.println(scB.peek() +"  " + i+ "scb");
               } else {
                   scA1.add(sc.pop()); 
                       // System.out.println(scA1.peek() + "   " +i + "sca1");
               }
            }
            sc = scA1;
       }


      while (!scB.empty()) {
          ans.add(scB.pop());
         // System.out.println(scB.pop() +"    /"+ i + "  scbpr");

      }
  }

      while (!sc.empty()) {
          ans.add(sc.pop());
      }
   return ans;
}

    }

  • ricardo1512
     + 0 comments

    Python

    def get_primes_till_N(N):
    """
    Creates an array of primes till N.
    """
    if N < 2:
        return []
    
    # Initialize a list to track prime numbers
    is_prime = [True] * (N + 1)
    is_prime[0], is_prime[1] = False, False  # 0 and 1 are not primes
    
    # Apply the Sieve of Eratosthenes algorithm
    for start in range(2, int(N**0.5) + 1):
        if is_prime[start]:
            for multiple in range(start*start, N + 1, start):
                is_prime[multiple] = False
    
    # Collect all prime numbers into a list
    primes = [num for num, prime in enumerate(is_prime) if prime]
    
    return primes

# Create array of primes till 10001:
primes = get_primes_till_N(10001)

def waiter(number, q):
    answers = list()
    A = number[:]

    for i in range(q):
        # Finish iteration if A is empty
        if not A:
            break
        # Store values in pile B
        B = [num for num in A if num % primes[i] == 0][::-1]
        # Remove values from pile A
        A = [num for num in A if num % primes[i] != 0][::-1]
        # Add values of pile B to answers:
        answers += B[::-1]
        
    return answers + A[::-1]