Linear solution for the problem

main.go

package main

import (
	"fmt"
	"math/rand"
	"time"
)

func main() {
	// Creating the building
	var building []int
	for c := 0; c < 100000; c++ {
		building = append(building, c)
	}
	// Generating the random targetFloor
	targetFloor := rand.New(rand.NewSource(time.Now().UnixNano())).Intn(len(building))
  	// Actual solution
	for f := range building {
		if building[f] == targetFloor {
			fmt.Println("Eggs start to break at floor ", f)
		}
	}
}