DocType - Basics of GoLang

solution.go

// 1. Write a struct in Go for a Person object that has a numeric Age attribute.
type Person struct {
	Age int
}

// 1.1) Write two functions in Go with the following function signature: func ([]Person) bool
// The first function should return true if there is a person who is exactly twice as old as any other person in the list, otherwise the function returns false.
func doubleAgeExists(persons []Person) bool {
	// Approach: Use a set (made from a GoLang Map DS) to store the age details
	// On one parse, check if age/2 or age*2 exists for the given age.
	ageSet := make(map[int]bool)
	for i := 0; i < len(persons); i++ {
		if ageSet[persons[i].Age*2] || ageSet[persons[i].Age/2] {
			return true
		} else {
			ageSet[persons[i].Age] = true
		}
	}
	return false
}

// The second function should return true if there is a person who is at least twice as old as any other person in the list, otherwise the function returns false.
func atleastDoubleAgeExists(persons []Person) bool {
	// Approach: Find the minimum and maximum aged persons in the struct
	// Check if the eldest in the group is atleast twice the youngest 
	min := persons[0].Age
	max := persons[1].Age

	for i := 0; i < len(persons); i++ {
		if persons[i].Age < min {
			min = persons[i].Age
		}

		if persons[i].Age > max {
			max = persons[i].Age
		}
	}

	return (2 * min) <= max
}


// 1.2) Are you familiar with computational complexity? If so, what is the time complexity of the functions you implemented?

// Time complexity is basically the time taken by the program to complete its execution -> usually denoted in the big-O notation.
// Time complexity of both the functions implemented above is O(n), as we have one loop and we iterate through it once and perform
// some task in constant time.