# Basic Calculator Program Using Java

• Difficulty Level : Hard
• Last Updated : 17 Nov, 2020

Create a simple calculator which can perform basic arithmetic operations like addition, subtraction, multiplication or division depending upon the user input.

Example :

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Enter the numbers:

2

2

Enter the operator (+,-,*,/)

+

The final result:

2.0 + 2.0 = 4.0

Approach Used:

• Take two numbers using the Scanner class. The switch case branching is used to execute a particular section.
• Using a switch case to evaluate respective operations.

## Java

 `// Java program for simple calculator`` ` `import` `java.io.*;``import` `java.lang.*;``import` `java.lang.Math;``import` `java.util.Scanner;``public` `class` `BasicCalculator {`` ` `    ``public` `static` `void` `main(String[] args)``    ``{``        ``// stores two numbers``        ``double` `num1, num2;`` ` `        ``// Take input from the user``        ``Scanner sc = ``new` `Scanner(System.in);`` ` `        ``System.out.println(``"Enter the numbers"``);`` ` `        ``// take the inputs``        ``num1 = sc.nextDouble();`` ` `        ``num2 = sc.nextDouble();`` ` `        ``System.out.println(``"Enter the operator (+,-,*,/)"``);`` ` `        ``char` `op = sc.next().charAt(``0``);`` ` `        ``double` `o = ``0``;`` ` `        ``switch` `(op) {`` ` `        ``// case to add two numbers``        ``case` `'+'``:`` ` `            ``o = num1 + num2;`` ` `            ``break``;`` ` `        ``// case to subtract two numbers``        ``case` `'-'``:`` ` `            ``o = num1 - num2;`` ` `            ``break``;`` ` `        ``// case to multiply two numbers``        ``case` `'*'``:`` ` `            ``o = num1 * num2;`` ` `            ``break``;`` ` `        ``// case to divide two numbers``        ``case` `'/'``:`` ` `            ``o = num1 / num2;`` ` `            ``break``;`` ` `        ``default``:`` ` `            ``System.out.println(``"You enter wrong input"``);`` ` `            ``break``;``        ``}`` ` `        ``System.out.println(``"The final result:"``);`` ` `        ``System.out.println();`` ` `        ``// print the final result``        ``System.out.println(num1 + ``" "` `+ op + ``" "` `+ num2``                           ``+ ``" = "` `+ o);``    ``}``}`

Output:

Enter the numbers:

2

2

Enter the operator (+,-,*,/)

+

The final result:

2.0 + 2.0 = 4.0

Time Complexity: O(1)

Auxiliary Space: O(1)

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