Compiles fine, but get an error when i enter a C value (e.g. 5 C) [closed]

When i enter a fahrenheit Value like 55 F it works pefectly fine, but if i type a Celcius value it gives me a massive error liek 5 C doesnt work. what am i missing, or what have i done wrong

import java.util.*;
public class tempConversion {  // The start of the main class 
     
     public static void main ( String[] args ) {
     
          
          
          System.out.println ( "Enter a Value and Temperature (e.g. 67 F): " );
          
          double val = 0;
          double c = 0.0;
          double f = 0.0;
          String temp = " ";
          
          Scanner scan = new Scanner( System.in );
          val = scan.nextDouble(); 
          temp = scan.next();  
          
          if (temp.equals( " F " ) )
          {
               f = val;
               c = ( 5.0 / 9.0 ) * ( f - 32 );    
               System.out.printf ( "%.2f Fahrenheit, = %.2f Celsius.\n", val, c );     
               
          }
          else
          {
               c = val;
               f = ( 1.8 * c * 32 );
               System.out.printf ( "%.2f Celcius, = %.2f Fahrenheit,\n", val, f );
          }
          
     }
}