goFloatsEx.go

package main

import "fmt"

// InterestRate returns the interest rate for the provided balance.
func InterestRate(balance float64) float32 {
	switch {
	case balance < 0: 
			return 3.213
	case balance >= 0 && balance < 1000:
			return 0.5
	case balance >= 1000 && balance < 5000:
			return 1.621
	}
	return 2.475
}

// Interest calculates the interest for the provided balance.
func Interest(balance float64) float64 {
	return balance * float64(InterestRate(balance)) / 100
}

// AnnualBalanceUpdate calculates the annual balance update, taking into account the interest rate.
func AnnualBalanceUpdate(balance float64) float64 {
	return balance + Interest(balance)
}

// YearsBeforeDesiredBalance calculates the minimum number of years required to reach the desired balance.
func YearsBeforeDesiredBalance(balance, targetBalance float64) int {
	c := 0
	for balance < targetBalance {
		balance = AnnualBalanceUpdate(balance)
		c++
	}
	return c
}

func main() {
	fmt.Println(InterestRate(200.75))
	fmt.Println(Interest(200.75))
	fmt.Println(AnnualBalanceUpdate(200.75))
	fmt.Println(YearsBeforeDesiredBalance(200.75, 214.88))
}

// Interest is Interesting