import sys
input = sys.stdin.readline

sys.setrecursionlimit(200020)

N=int(input())
C=[input().split() for i in range(N)]

USE=[0]*N

def dfs(x):
    USE[x]=1
    ANS=[]
    for i in range(4):
        if C[x][i]=="H":
            continue
        k=int(C[x][i])-1
        
        if USE[k]==1:
            continue

        ANS.append("(")
        ANS.append("".join(dfs(k)))
        ANS.append(")")

    ANS.append("methyl")

    #print(ANS)

    return ANS

ANS=dfs(0)

ANS[-1]="methane"

print("".join(ANS))