java program to make a calculator code example
Example 1: how to make a calculator in java
package javaCode;
import java.util.Scanner;
public class testCode {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.println("Would you like to Add, Subtract, Divide, or Multiply?");
String mathType = scan.next();
if (mathType.equalsIgnoreCase("add")) {
System.out.println("Whats the first number you want to add?");
int firstNumber = scan.nextInt();
System.out.println(firstNumber + " + ");
System.out.println("Enter your second number");
int secondNumber = scan.nextInt();
System.out.println(firstNumber + " + " + secondNumber + " =");
System.out.println(firstNumber + secondNumber);
} else if (mathType.equalsIgnoreCase("subtract")) {
System.out.println("Whats the first number you want to subtract?");
int firstNumber = scan.nextInt();
System.out.println(firstNumber + " - ");
System.out.println("Enter your second number");
int secondNumber = scan.nextInt();
System.out.println(firstNumber + " - " + secondNumber + " =");
System.out.println(firstNumber - secondNumber);
} else if (mathType.equalsIgnoreCase("divide")) {
System.out.println("Whats the first number you want to divide?");
int firstNumber = scan.nextInt();
System.out.println(firstNumber + " % ");
System.out.println("Enter your second number");
int secondNumber = scan.nextInt();
System.out.println(firstNumber + " % " + secondNumber + " =");
System.out.println(firstNumber / secondNumber);
} else if (mathType.equalsIgnoreCase("multiply")){
System.out.println("Whats the first number you want to multiply?");
int firstNumber = scan.nextInt();
System.out.println(firstNumber + " x ");
System.out.println("Enter your second number");
int secondNumber = scan.nextInt();
System.out.println(firstNumber + " x " + secondNumber + " =");
System.out.println(firstNumber * secondNumber);
}
}
}
Example 2: simple calculator program in java
import java.util.Scanner;
public class Calculator {
public static void main(String[] args) {
Scanner reader = new Scanner(System.in);
System.out.print("Enter two numbers: ");
double first = reader.nextDouble();
double second = reader.nextDouble();
System.out.print("Enter an operator (+, -, *, /): ");
char operator = reader.next().charAt(0);
double result;
switch(operator)
{
case '+':
result = first + second;
break;
case '-':
result = first - second;
break;
case '*':
result = first * second;
break;
case '/':
result = first / second;
break;
default:
System.out.printf("Error! operator is not correct");
return;
}
System.out.printf("%.1f %c %.1f = %.1f", first, operator, second, result);
}
}