Arithmetic Operators in Go: + - * / and %

TL ; DR:

• We can tell computers to perform calculations for us using +, -, *, and /:

  fmt.Println(2 + 6)  // Prints 8
  fmt.Println(10 - 7) // Prints 3
  fmt.Println(3 * 3)  // Prints 9
  fmt.Println(6 / 2)  // Prints 3
  

  
  
  

• We can also use variables. In these examples, Go replaces variable num with its value 6 to do the calculations:

  num := 6
  fmt.Println(num + 5) // Prints 11
  fmt.Println(10 - num) // Prints 4
  fmt.Println(3 * num) // Prints 18
  fmt.Println(num / 2) // Prints 3
  

  
  

Full lesson:

Computers excel at performing calculations. These calculations can be performed directly with numbers or with variables that store numeric values.

Arithmetic operators are used with numeric values to perform common mathematical operations:

Performing arithmetic on variables does not change the variable. You update a variable only with assignment, such as = or +=.

Let's go through some examples together to better understand how each operator works.

Addition

a := 2
b := 3

fmt.Println(a + b)  // Output: 5
fmt.Println(a + 10) // Output: 12

Subtraction

a := 2
b := 3

fmt.Println(a - b)  // Output: -1
fmt.Println(10 - b) // Output: 7

Multiplication

a := 2
b := 3

fmt.Println(a * 5)     // Output: 10
fmt.Println(2 * a * b) // Output: 12

Division

In Go, division between integers returns only the integral part of the result:

a := 2
b := 3

fmt.Println(20 / 3) // Output: 6
fmt.Println(b / a)  // Output: 1

If we want a decimal result, at least one of the values must be a floating-point type:

a := 2
b := 3

fmt.Println(7.0 / 3.0)             // Output: 2.3333333333333335
fmt.Println(float64(b) / float64(a)) // Output: 1.5

Assignment
Follow the Coding Tutorial and let's practice with arithmetic operators!

Hint
Look at the examples above if you get stuck.