package main

import . "fmt"

func main() {
	var a,b,c int
	Scan(&a,&b,&c)
	ans:=int(1e9)
	for price:=1;price<=a+b*10;price++ {
		for pa:=0;pa<=a;pa++ {
			for pb:=0;pb<=b;pb++ {
				paid:=pa+pb*10
				if paid<price {
					continue
				}
				back:=paid-price
				coin:=(a-pa)+(b-pb)+back/10+back%10
				if coin!=c {
					continue
				}
				if price<ans {
					ans=price
				}
			}
		}
	}
	if ans<1e9 {
		Println(ans)
	} else {
		Println("Impossible")
	}
}