the weirdest problem i came across in java about scanner string

[amr talaat]

look at this code

import java.util.Scanner;
public class NewMain {

   
    public static void main(String[] args) {
          Scanner inp=new Scanner(System.in);
        System.out.println("how many times do you want to enter your name and age ");
        int x=inp.nextInt();
      
        
       
        for(int i=0;i<x;i++)
        {
            System.out.println("enter your name");
   String  s=inp.nextLine();
      System.out.println("enter your  age");
     int a=inp.nextInt();
        }
      
      
    }
}

the problem is that when i complie it and run it this is the result

how many times do you want to enter your name and age

console input{ i type 2 for example}

enter your name
enter your age
{ console input : }

enter your name
enter your age
{console input: }



it overlooks the input for name every time looping

why is that ???


when i change name from String to int and change nextline to nextInt

it do fine

whats wrong there ???

[Steve Luke]

This is a pretty common problem with the Scanner. When you do the console input, you press the enter key, effectively adding a new line to the input. When you first read the number from the input you do nextInt(), which reads the number but not the new-line. You then ask for the nextLine(), and since there is a new-line waiting in the input stream it immediately returns (with an empty String). You next ask for a nextInt() which lets you input a number, after which you again press the enter key, which enters a new-line after the number, and again the number is consumed by nextInt() but the new-line is not so the process occurs over and over again.

What you need to do is add an additional nextLine() after each nextInt().

[amr talaat]

thanks very much this solve the problem