S=list(input())
def operate(S,T0,T1):
    queue=[]
    cnt=0
    for s in S:
        queue.append(s)
        while len(queue)>=len(T0) and queue[len(queue)-len(T0):]==T0:
            for _ in range(len(T0)):
                queue.pop()
            for t in T1:
                queue.append(t)
            cnt+=1
    return queue,cnt
ans=0
S,cnt=operate(S,list("phnom"),list("penh"))
ans+=cnt
if "h" in S or "e" in S:
    S,_=operate(S,["h"],[])
    S,_=operate(S,["e"],["h"])
    ans+=1
queue=[]
for s in S:
    queue.append(s)
    if len(queue)>=5 and queue[-5:]==list("phnom"):
        for _ in range(2):
            queue.pop()
        ans+=2
if "h" in queue:
    ans+=1
print(ans)