import java.util.Scanner;

class Main{
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		long n=sc.nextLong(),z1=sc.nextLong(),zn=0,t,i;
		for(i=1;i<n;i++) {
			if(i>n-2) zn=sc.nextLong();
			else t=sc.nextLong();
		}
		sc.close();
		System.out.print(zn+"/"+z1);
	}
}