Simple Calculator Java Coding Errors -

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• simple java calculator 10 answers

trying make simple calculator in java keep getting errors when try compile it. not sure if it's coding or doing when compile it. appreciated!

import java.util.scanner;  class simple calculator { // simple calculator public static void main(string args[]){    system.out.println("my simple calculator\n");        scanner bucky= new scanner(system.in);    double fnum,snum,ans;    system.out.print("enter first , second " +            "number : ");    a=bucky.nextfloat(); //assign numbers    b=bucky.nextdouble(); // respective variable    system.out.println("what operation u want " +                                    "perform");    string operation;    operation=bucky.next();    switch(operation) {    case "+":        ans=a + b;    system.out.print("sum of 2 inputs = ");            system.out.print(ans);            break;    case "-":        ans=a - b;     system.out.print("subtraction of 2 inputs = ");             system.out.print(ans);             break;    case "*":        ans=a * b;     system.out.print("multiplication of 2 inputs = ");             system.out.print(ans);        break;    case "/":        ans=a / b;     system.out.print("division of 2 inputs = ");             system.out.print(ans);             break; default : system.out.println("give proper operation " +                         "symbol ");                  break; // not required    }  } } 

two compilation errors:

• your class name has whitespace in it: class simple calculator isn't valid, because "calculator" isn't recognized token. try: class simplecalculator. make public , change name of file match. (simplecalculator.java).
• you declare variables a , b don't give them types. use float = ... , double b = .... 1 float , other double strange, pressing on...

other new-to-java issues note:

• you never close bucky, scanner. resource leak, , in bigger application major bug. add bucky.close() after read last line it, after operation = bucky.next()
• the name bucky tells me absolutely nothing or use is. try use descriptive variable names. (the main exception being single letter names loop indices, etc).
• fnum , snum local variables declare never use. perhaps rid of them?

here's code edits made:

import java.util.scanner;  public class simplecalculator { // simple calculator     public static void main(string args[]){         system.out.println("my simple calculator\n");         scanner bucky= new scanner(system.in);         double ans;         system.out.print("enter first , second " +                 "number : ");         float a=bucky.nextfloat(); //assign numbers         double b=bucky.nextdouble(); // respective variable         system.out.println("what operation u want " +                 "perform");         string operation;         operation=bucky.next();         bucky.close();         switch(operation) {         case "+":             ans=a + b;             system.out.print("sum of 2 inputs = ");             system.out.print(ans);             break;         case "-":             ans=a - b;             system.out.print("subtraction of 2 inputs = ");             system.out.print(ans);             break;         case "*":             ans=a * b;             system.out.print("multiplication of 2 inputs = ");             system.out.print(ans);             break;         case "/":             ans=a / b;             system.out.print("division of 2 inputs = ");             system.out.print(ans);             break;         default : system.out.println("give proper operation " +                 "symbol ");          break; // not required         }     } } 

i able compile in terminal no trouble.