S=input()
LEN=len(S)
S+="z"*100

LEN=len(S)

L=[]
for i in range(LEN):
    if S[i:i+3]=="phn":
        s=0
        j=i+3
        while S[j:j+2]=="om":
            s+=1
            j+=2
        L.append(s)

if L==[]:
    ANS=0
else:
    ANS=max(L)+sum(L)+1

T=""
for s in S:
    if s=="h":
        continue
    if s=="e":
        T+="h"
    else:
        T+=s

if S==T:
    print(ANS)
    
else:    
    L=[]
    for i in range(len(T)):
        if T[i:i+3]=="phn":
            s=0
            j=i+3
            while T[j:j+2]=="om":
                s+=1
                j+=2
            L.append(s)

    if L==[]:
        ANS2=0
    else:
        ANS2=max(L)+sum(L)+2

    print(max(ANS,ANS2))