CODEWITHSUNDEEP
javaarraysmethodsarraylist
Sjanes227
Sjanes227

Reputation: 17

Adding numbers Into ArrayList Using a for Loop - Java

A supermarket wants to reward its best customer of each day, showing the customer’s name on a screen in the supermarket. For that purpose, the customer’s purchase amount is stored in an ArrayList and the customer’s name is stored in a corresponding ArrayList. Implement a method public static String nameOfBestCustomer(ArrayList sales, ArrayList customers) that returns the name of the customer with the largest sale. Write a program that prompts the cashier to enter all prices and names, adds them to two array lists, calls the method that you implemented, and displays the result. Use a price of 0 as a sentinel.

So far I'm having a problem inputing the numbers/ names into the array by keyboard using a for loop. This is what i have so far;

import java.util.Arrays;
import java.util.ArrayList;
import java.util.Scanner;

public class TopCustomer {

    public static String nameOfBestCustomer(ArrayList<Double> sales, ArrayList<String> customers) {

}

public static void main (String [] args){
    ArrayList<Double> sales = new ArrayList<Double>();
    ArrayList<String> customer = new ArrayList<String>();
    Scanner in = new Scanner(System.in);        
    System.out.print("How many Customers are there?");
    int num = in.nextInt();

    for (int i = 1; num <= i; i++) {
        System.out.print("Enter name of customer " + i + ": \n");
        customer.add(i) = in.nextString();
        System.out.print("Enter how much customer " + i + ": \n");
        sales.add(i) = in.nextDouble(); 
    }
}

}

Upvotes: 0

Views: 2562

Answers (2)

mig
mig

Reputation: 152

you have 2 errors here i have corrected them below

for (int i = 0; i < num; i++){
    System.out.print("Enter name of customer " + (i+1) + ": \n");
    customer.add(in.next());
    System.out.print("Enter how much customer " + (i+1) + ": \n");
    sales.add(in.nextDouble()); 
}

first your for loop should be formatted the way i presented becuase otherwise it was always ending instantly unless there is only 1 customer and also the .add() method you were using automatically adds what is inside to the end of the array list.

Upvotes: 2

nook
nook

Reputation: 2396

Your error is here:

for (int i = 1; num <= i; i++) {

If a user inputs a num greater than 1, this loop will terminate immediately. Want you want it is:

for (int i = 1; i <= num; i++) {

You are also adding in the data wrong. Instead of this:

customer.add(i) = in.nextString();

and 

  sales.add(i) = in.nextDouble();

Do,

customer.add(in.nextString())

and

sales.add(in.nextDouble());

Upvotes: 2

Related Questions