# MERGE IT


'''n=int(input())
for i in range(0,n):
    o=int(input())
    p=input().rstrip().split(' ')
    l=[0]*3;
    for j in range(0,len(p)):
        l[(int(p[j])%3)]+=1;
    s=0;
    s+=l[0];
    s+=min(l[1],l[2])
    if min(l[1],l[2])==l[2]:
        l[1]-=l[2]
        s+=(l[1]//3)
    elif min(l[1],l[2])==l[1]:
        l[2]-=l[1]
        s+=(l[2]//3)
    print(s)'''

# LOSE IT

s=input().rstrip()
x=list(s)
T=0;
for i in range(0,len(x)):
    if x[i]=='o':
        T+=1;
T+=(15-len(x))
if T>=8:
    print("YES")
else:
    print("NO") '''n=int(input())
for i in range(0,n):
    o=int(input())
    p=input().rstrip().split(' ')
    l=[0]*3;
    for j in range(0,len(p)):
        l[(int(p[j])%3)]+=1;
    s=0;
    s+=l[0];
    s+=min(l[1],l[2])
    if min(l[1],l[2])==l[2]:
        l[1]-=l[2]
        s+=(l[1]//3)
    elif min(l[1],l[2])==l[1]:
        l[2]-=l[1]
        s+=(l[2]//3)
    print(s)''' s=input().rstrip() s input().rstrip() ().rstrip () input rstrip x=list(s) x list(s) list s T=0 T 0 for i in range(0,len(x)):
    if x[i]=='o':
        T+=1; i range(0,len(x)) range 0 len(x) len x if x[i]=='o':
        T+=1; x[i]=='o' x[i] x i 'o' T+=1 T 1 T+=(15-len(x)) T 15-len(x) 15 len(x) len x if T>=8:
    print("YES")
else:
    print("NO") T>=8 T 8 print("YES") print "YES" print("NO") print "NO" T=0 0 T T+=1 1 T s=input().rstrip() input().rstrip() s T+=(15-len(x)) 15-len(x) T x=list(s) list(s) x
# MERGE IT


'''n=int(input())
for i in range(0,n):
    o=int(input())
    p=input().rstrip().split(' ')
    l=[0]*3;
    for j in range(0,len(p)):
        l[(int(p[j])%3)]+=1;
    s=0;
    s+=l[0];
    s+=min(l[1],l[2])
    if min(l[1],l[2])==l[2]:
        l[1]-=l[2]
        s+=(l[1]//3)
    elif min(l[1],l[2])==l[1]:
        l[2]-=l[1]
        s+=(l[2]//3)
    print(s)'''

# LOSE IT

s=input().rstrip()
x=list(s)
T=0;
for i in range(0,len(x)):
    if x[i]=='o':
        T+=1;
T+=(15-len(x))
if T>=8:
    print("YES")
else:
    print("NO")
