package main
 
	import (
		"fmt"
		"unicode"
	)
 
	func main() {
		phrase := "is this loss?"
		//result := strings.Builder{} // You must be older than go1.10 :(
		result := make([]rune, len(phrase))
 
		for i, j := range phrase {
			if i%2 == 1 {
				//result.WriteRune(unicode.ToLower(j))
				result[i] = unicode.ToLower(j)
			} else {
				//result.WriteRune(unicode.ToUpper(j))
				result[i] = unicode.ToUpper(j)
			}
		}
		//fmt.Println(result.String())
		fmt.Println(string(result))
	}

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