Go has some similarity with python and a lot are different, fortunately during my university I was forced to take up foundation of programming which I have learned C.

So below are the codes which I have put in comments to explain the statements.

**simplemath package**

package simplemath // my custom 2 integers math package. // Add(), the A is capital hence can be "exported" to other package out of simplemath package. // (a, b int), this says variable a and b are int type. then int after the paranthesis is to // tell Go that the return value is an int. // since i did not specify the return variable name, i need to return the result a + b func Add(a, b int) int { return a + b } func Subtract(a, b int) int { return a - b } // This function has declared the return variable name - product which is type int. // hence my multiplication has to be stored in the product variable // but my return statement can just be return itself. func Multiply(a, b int) (product int) { product = a * b return } func Divide(a, b int) (division int) { division = a / b return }

**Main package that imports simplemath and runs it**

package main import ( "fmt" // bulit-in formatting package "lab1/simplemath" // custom math package ) func main() { /* assignment of values to variables can be done in several ways */ // Declare a variable addition and explicitly give int as the data type. // If int type is not specified then Go will assume int64 if on 64-bit system // and int32 if on 32-bit system var addition int // assign the result from the package function into the variable. // = is used for assignment only after the variable addition is declared. addition = simplemath.Add(5, 10) // Else you should assign value in this way. // This is a shorthand for var multiplication = simplemath.Multiply(2, 8) // When := is used, it declares the variable and do the assignment at the same time. multiplication := simplemath.Multiply(2, 8) // This is to declare a variable and explicitly declare the data type as int. // the shorthand for this is division := simplemath.Divide(10, 2) var division int = simplemath.Divide(10, 2) // This is another way to declare and assign values to variable without declaring data type. // Base on the return value the data type is figured by Go. var subtraction = simplemath.Subtract(20, 5) /* fmt.Printf is used to format the string. %d is decimal, base 10, numbers that are divisible by 10, if you see 0 at the trailing number it is sure a decimal. each number is between 0 and 9. Example 70 = 7x 10^1 + 0 x 10^0 Another Example 810 = 8 x 10^2 + 1 x 10^1 + 0 x 10^0 %o this is octal, base 8, each number between 0 and 7, example octal of 144 = 1 x 8^2 + 4 x 8^1 + 4 x 8^0 is a decimal of 100. %b is base 2, only between 0 and 1. Example 1001 = 1 x 2^3 + 0 x 2^2 + 0 x 2^1 + 1 x 2^0 = decimal 9 %t is boolean either True or False. See https://golang.org/pkg/fmt/ */ fmt.Printf("Addition is %d\n", addition) fmt.Printf("Multiplication is %d\n", multiplication) fmt.Printf("Division is %d\n", division) fmt.Printf("Subtraction is %d", subtraction) }

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