42 lines
919 B
Go
42 lines
919 B
Go
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// For more tutorials: https://blog.learngoprogramming.com
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//
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// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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package main
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import (
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"fmt"
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)
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// ---------------------------------------------------------
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// EXERCISE
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// 1. Get the radius from the command-line
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// 2. Convert it to a float64
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// 3. Calculate the surface area of a sphere
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//
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// SPHERE SURFACE AREA FORMULA
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// area = 4πr²
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// https://en.wikipedia.org/wiki/Sphere#Surface_area
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//
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// RESTRICTION
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// Use `math.Pow` to calculate the area
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// Read its documentation to see how it works.
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// https://golang.org/pkg/math/#Pow
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//
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// EXPECTED OUTPUT
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// 1256.64
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// ---------------------------------------------------------
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func main() {
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var radius, area float64
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// ADD YOUR CODE HERE
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// ...
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// DO NOT TOUCH THIS
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fmt.Printf("radius: %g -> area: %.2f\n", radius, area)
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}
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