Print Inverted Hash Collection in Go

In golang, we can print the inverted hash collection using the inverted mapping method. Hashmap stored the data in pair of key:Value in hash collection and that reduces the execution time. In this article we are going to see two different example to understand how to create a golang program that will print an inverted hash collection.

Syntax

func make ([] type, size, capacity)

The make function in go language is used to create an array/map it accepts the type of variable to be created, its size and capacity as arguments.

func len(v Type) int

The len() function is used to get the length of a any parameter. It takes one parameter as the data type variable whose length we wish to find and returns the integer value which is the length of the variable.

Algorithm

• Import the desired packages in the program

• Create a main function

• In that particular function create a hashmap

• Then, create an inverted map using internal functions

• Print the inverted map on the console

Example 1

In this example, we will create a hashmap and an additional map named inverted to get the inverted output i.e. key is assigned to value. The hashmap will be iterated to get the inverted output in every iteration. Let's understand this example and have a close look at the code and the algorithm.

//Golang program to print the inverted hash collection
package main

import "fmt"

//Main to execute the program
func main() {
   // Create a map with keys of type string and values of type int
   hashmap := map[string]int{"apple": 100, "mango": 180, "banana": 120}
   
   // Create a new map with inverted keys and values
   inverted := make(map[int]string)
   for k, element := range hashmap {
      inverted[element] = k
   }
   
   // Print the inverted map
   fmt.Println("This is the following inverted map:")
   fmt.Println(inverted)
}

Output

This is the following inverted map:
map[100:apple 120:banana 180:mango]

Example 2

In this illustration, we will use len(map) in the make function to create inverted map which will be used to store the inverted key:value pairs. The output will be an inverted map printed on the console using fmt package. Let's see the execution via code and the algorithm.

//Golang program to print the inverted hash collection
package main

import "fmt"

//Main function to execute the program
func main() {
   // Create a map with keys of type string and values of type int
   hashmap := map[string]int{"apple": 100, "mango": 120, "banana": 130}
   
   // Create a new map with inverted keys and values
   inverted := make(map[int]string, len(hashmap))
   for k, element := range hashmap {
      inverted[element] = k
   }
   
   // Print the inverted map
   fmt.Println("The inverted map is presented as follows:")
   fmt.Println(inverted)
}

Output

The inverted map is presented as follows:
map[100:apple 120:mango 130:banana]

Conclusion

We executed the program of printing the inverted hash collection using two examples. In the first example we created the additional map without using len(hashmap) whereas in the second example we created the map using len(hashmap) function.