a=input('')
j=0
p=0
t=[]
f=[]
e=[]
k=[]
r=0
x=0
y=0
w=0
for i in range(len(a)):
    if(a[p]=='h'):
        t.append(p)
        break
    p=p+1
if(len(t)>0):
    for j in range(len(a)):
        if(a[r]=='e' and t[0]<r):
            f.append(r)
            break
        r=r+1
if(len(f)>0):
    for jkl in range(len(a)):
        if(a[x]=='l' and f[0]<x):
            e.append(x)
            if(len(e)==2):
                break
        x=x+1
if(len(e)>0):
    for jpm in range(len(a)):
        if(a[y]=='o' and e[0]<y):
            k.append(y)
            break
        y=y+1
if(len(t)>0 and len(f)>0 and len(e)>1 and len(k)>0):
    print('YES')
else:
    print('NO')



    
        

        
