Map, HashMap, Scanner

Guest User

5y1.5kJava

This is what the output should be::

This is my code:

first problem is that i cant combine string and integer(ex. 555-999 )

second problem is the output, two name is showing (ex. name: name:)

what is the right code for it.. thank you for the answer

6 Replies

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Aman Gupta5y ago
Accepted answer
Hi Justine,

here is the solution to your problem or a file is attached for your reference.
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;
import java.util.Set;
public class Test {
public static void main(String[] args) throws Exception
{
Scanner sc = new Scanner(System.in); //for input from user
Map hm = new HashMap();
//loop to enter the desired values
for(int i=0; i<3;i++)
{
System.out.print((i+1)+"."+" student number: ");
int num = sc.nextInt(); //int value
sc.nextLine(); // to eliminate any cohesion
System.out.print("name: ");
String name = sc.nextLine(); // string value
hm.put(num, name); //add value to hashmap
}
//Fetch values in an ordered manner
Set id = hm.keySet();
for(Integer i : id)
{
System.out.println(i + "\t" + hm.get(i)); //each pair in new line
}
System.out.println();
}
}
Aman Gupta5y ago
Yes for that, take user input in other variable (say id) and pass that like this hm.remove(id). Remember id as integer variable.
Aman Gupta5y ago
hm.remove(Object key) will work only if you pass Key as paraneter. Here pass "hm.remove(5252)" and your data with value Mario will be removed.
Guest User5y ago
hey Aman, sorry for the trouble.. what you mean is i should type hm.remove(5252) and hm.remove(dfd).?
Aman Gupta5y ago
Hi Justin, Always remember you can only remove the object from hashmap entry through, hashmap.remove(Object key) If key is valid then your data will be removed from map else it will return Null.So in this case you should use hm.remove(2018-0134), this will work as well as for confirmation, print the new map again.
Guest User5y ago
I'm trying to remove the third output of keys and value using the hm.remove(3); but it wont work
please help.. i badly really want to know..