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

LEN=len(S)

MAX=0
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
        MAX=max(s,MAX)

if MAX==0:
    ANS=0
else:
    ANS=MAX*2+1

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

if S==T:
    print(ANS)
    
else:    
    MAX=0
    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
                
            MAX=max(s,MAX)

    if MAX==0:
        print(max(ANS,1))
    else:
        print(max(ANS,MAX*2+2))