Valera the Horse is going to the party with friends. He has been following the fashion trends for a while, and he knows that it is very popular to wear all horseshoes of different color. Valera has got four horseshoes left from the last year, but maybe some of them have the same color. In this case he needs to go to the store and buy some few more horseshoes, not to lose face in front of his stylish comrades.

Fortunately, the store sells horseshoes of all colors under the sun and Valera has enough money to buy any four of them. However, in order to save the money, he would like to spend as little money as possible, so you need to help Valera and determine what is the minimum number of horseshoes he needs to buy to wear four horseshoes of different colors to a party.

Input

The first line contains four space-separated integers s1, s2, s3, s4 (1 ≤ s1, s2, s3, s4 ≤ 109) — the colors of horseshoes Valera has.

Consider all possible colors indexed with integers.

Output

Print a single integer — the minimum number of horseshoes Valera needs to buy.

Examples

Input

1 7 3 3


Output

1


Input

7 7 7 7


Output

3
'''
def main():
    from sys import stdin,stdout
if __name__=='__main__':
    main()
'''
#1A
'''
def main():
    from sys import stdin,stdout
    from math import ceil
    n,m,a=map(int,stdin.readline().split())
    stdout.write(str(ceil(n/a)*ceil(m/a)))
if __name__=='__main__':
    main()
'''
#4A
'''
def main():
    from sys import stdin,stdout
    i=int(stdin.readline())
    if i&1:
        stdout.write('NO\n')
    else:
        if i//2 >1:
            stdout.write('YES\n')
        else:
            stdout.write('NO\n')
if __name__=='__main__':
    main()
'''
#71A
'''
def main():
    from sys import stdin,stdout
    for _ in range(int(stdin.readline())):
        s=stdin.readline().strip()
        if len(s) <=10:
            stdout.write(s+'\n')
        else:
            stdout.write(s[0]+str(len(s[1:-1]))+s[-1]+'\n')
if __name__=='__main__':
    main()
'''
#158A
'''
def main():
    from sys import stdin,stdout
    n,k=map(int,stdin.readline().split())
    a=list(map(int,stdin.readline().split()))
    count=0
    for i in range(n):
        if a[i] and a[i]>=a[k-1]:
            count+=1
    stdout.write(str(count))
if __name__=='__main__':
    main()
'''
#188A
'''
def main():
    from sys import stdin,stdout
    s=stdin.readline().strip()
    t=''
    s=s.lower()
    for i in s:
        if i not in 'aeiouy':
            t+='.'+i
    stdout.write(t)
if __name__=='__main__':
    main()
'''
#50A
'''
def main():
    from sys import stdin,stdout
    n,m=map(int,stdin.readline().split())
    stdout.write(str((n*m)//2))
if __name__=='__main__':
    main()
'''
#231A
'''
def main():
    from sys import stdin,stdout
    count=0
    for _ in range(int(stdin.readline())):
        if sum(list(map(int,stdin.readline().split())))>=2:
            count+=1
    stdout.write(str(count))
if __name__=='__main__':
    main()
'''
#282A
'''
def main():
    from sys import stdin,stdout
    x=0
    for _ in range(int(stdin.readline())):
        s=stdin.readline().strip()
        if '++' in s:
            x+=1
        elif '--' in s:
            x-=1
    stdout.write(str(x))
if __name__=='__main__':
    main()
'''
#158B
'''
def main():
    from sys import stdin,stdout
    n=int(stdin.readline())
    l=sorted(list(map(int,stdin.readline().split())))
    counter=l.count(4)
    l=l[:n-counter]
    i=0
    while len(l):
        if len(l)==1:
            counter+=1
            break
        
    stdout.write(str(counter))
if __name__=='__main__':
    main()
'''
#96A
'''
def main():
    from sys import stdin,stdout
    s=stdin.readline().strip()
    count=1
    flag=0
    for i in range(1,len(s)):
        if s[i]==s[i-1]:
            count+=1
            if count >=7:
                flag=1
                break
        else:
            count=1
    if flag:
        stdout.write('YES')
    else:
        stdout.write('NO')
if __name__=='__main__':
    main()
'''
#116A
'''
def main():
    from sys import stdin,stdout
    maxim=0
    total=0
    for _ in range(int(stdin.readline())):
        a,b=map(int,stdin.readline().split())
        total+=(b-a)
        if total >maxim:
            maxim=total
    stdout.write(str(maxim))
if __name__=='__main__':
    main()
'''
#112A
'''
def main():
    from sys import stdin,stdout
    s=stdin.readline().strip().lower()
    t=stdin.readline().strip().lower()
    if s==t:
        stdout.write('0')
    elif s < t:
        stdout.write('-1')
    else:
        stdout.write('1')
if __name__=='__main__':
    main()
'''
#339A
'''
def main():
    from sys import stdin,stdout
    l=list(map(str,stdin.readline().strip().split('+')))
    l.sort()
    stdout.write('+'.join(l))
if __name__=='__main__':
    main()
'''
#131A
'''

def main():
    from sys import stdin,stdout
    s=stdin.readline().strip()
    if s.isupper():
        stdout.write(s.lower())
    elif (s[0].islower() and s[1:].isupper()) or (len(s)==1 and s.islower()):
        stdout.write(s.title())
    else:
        stdout.write(s)
if __name__=='__main__':
    main()
'''
#266A
'''
def main():
    from sys import stdin,stdout
    n=int(stdin.readline())
    count=0
    s=stdin.readline().strip()
    for i in range(1,n):
        if s[i]==s[i-1]:
            count+=1
    stdout.write(str(count))
if __name__=='__main__':
    main()
'''
#133A
'''
def main():
    from sys import stdin,stdout
    s=stdin.readline().strip()
    if 'H' in s or 'Q' in s or '9' in s:
        stdout.write('YES')
    else:
        stdout.write('NO')
if __name__=='__main__':
    main()
'''
#281A
'''
def main():
    from sys import stdin,stdout
    s=stdin.readline().strip()
    stdout.write(s[0].upper()+s[1:])
if __name__=='__main__':
    main()
'''
#58A
'''
def main():
    from sys import stdin,stdout
    test='hello'
    s=stdin.readline().strip()
    while len(test) and len(s):
        if test[0]==s[0]:
            test=test[1:]
            s=s[1:]
        else:
            s=s[1:]
    if test=='':
        stdout.write('YES')
    else:
        stdout.write('NO')
if __name__=='__main__':
    main()
'''
#236A
'''
def main():
    from sys import stdin,stdout
    if len(set(stdin.readline().strip())) & 1:
        stdout.write('IGNORE HIM!')
    else:
        stdout.write('CHAT WITH HER!')
if __name__=='__main__':
    main()
'''
#467A
'''
def main():
    from sys import stdin,stdout
    count=0
    for _ in range(int(stdin.readline())):
        a,b=map(int,stdin.readline().split())
        if b-a>=2:
            count+=1
    stdout.write(str(count))
if __name__=='__main__':
    main()
'''
#148A
'''
def main():
    from sys import stdin,stdout
    k=int(stdin.readline())
    l=int(stdin.readline())
    m=int(stdin.readline())
    n=int(stdin.readline())
    d=int(stdin.readline())
    count=0
    for i in range(1,d+1):
        if i % k and i % l and i % m and i % n:
            count+=1
    stdout.write(str(d-count))
if __name__=='__main__':
    main()
'''
#263A
'''
def main():
    from sys import stdin,stdout
    for i in range(5):
        a=list(map(int,stdin.readline().split()))
        try:
            x=a.index(1)+1
            y=i+1
        except:
            g=''
    stdout.write(str(abs(x-3)+abs(y-3)))
if __name__=='__main__':
    main()
'''
#546A
'''
def main():
    from sys import stdin,stdout
    k,n,w=map(int,stdin.readline().split())
    m=(w*(w+1)*k)//2
    if m<=n:
        stdout.write('0')
    else:
        stdout.write(str(m-n))
if __name__=='__main__':
    main()
'''
#136A
'''
def main():
    from sys import stdin,stdout
    n=int(stdin.readline())
    l=list(map(int,stdin.readline().split()))
    p=[0 for _ in range(n)]
    for i in range(n):
        p[l[i]-1]=i+1
    stdout.write(' '.join(str(x) for x in p))
if __name__=='__main__':
    main()
'''
#122A
'''
def main():
    l=[]
    for i in range(4,1001):
        s=str(i)
        flag=1
        for element in s:
            if element !='4' and element !='7':
                flag=0
                break
        if flag:
            l.append(i)
    from sys import stdin,stdout
    n=int(stdin.readline())
    for i in l:
        if n%i==0:
            stdout.write('YES')
            return
    stdout.write('NO')
if __name__=='__main__':
    main()
'''
#266B
'''
def main():
    from sys import stdin,stdout
    n,x=map(int,stdin.readline().split())
    s=stdin.readline().strip()
    for _ in range(x):
        s=s.replace('BG','GB')
    stdout.write(s)
if __name__=='__main__':
    main()
'''
#271A
'''
def main():
    from sys import stdin,stdout
    n=int(stdin.readline())
    n+=1
    while True:
        if len(str(n))==len(set(str(n))):
            break
        else:
            n+=1
    stdout.write(str(n))
if __name__=='__main__':
    main()
'''
#41A
'''
def main():
    from sys import stdin,stdout
    a=stdin.readline().strip()
    b=stdin.readline().strip()
    if a==b[-1::-1]:
        stdout.write('YES')
    else:
        stdout.write('NO')
if __name__=='__main__':
    main()
'''
#160A
'''
def main():
    from sys import stdin,stdout
    n=int(stdin.readline())
    l=sorted(list(map(int,stdin.readline().split())))
    p=l[-1]
    lsum=sum(l[:-1])
    l=l[:-1]
    count=1
    while lsum >= p:
        p+=l[-1]
        lsum-=l[-1]
        l=l[:-1]
        count+=1
    stdout.write(str(count))
if __name__=='__main__':
    main()
'''
#110A
'''
def main():
    from sys import stdin,stdout
    s=stdin.readline().strip()
    k=s.count('4')+s.count('7')
    if  k==4 or k==7:
        stdout.write('YES')
    else:
        stdout.write('NO')
if __name__=='__main__':
    main()
'''
#100989A
'''
def main():
    from sys import stdin,stdout
    stdout.write(str(int(stdin.readline())+1))
if __name__=='__main__':
    main()
'''
#100989C
'''
def main():
    from sys import stdin,stdout
    count=0
    for _ in range(int(stdin.readline())):
        a,b=map(int,stdin.readline().split())
        count+=(b-a)
    stdout.write(str(count))
if __name__=='__main__':
    main()
'''
#100989D
'''
def main():
    from sys import stdin,stdout
    n,q=map(int,stdin.readline().split())
    l=sorted(list(map(int,stdin.readline().split())))
    o=[]
    for i in range(n):
        o.append(0)
    while q:
        a,b=map(str,stdin.readline().split())
        if a =='in':
            b=int(b)
            flag=0
            for i in range(n):
                if b<=l[i] and o[i]==0:
                    o[i]=1
                    flag=1
                    break
            if flag:
                stdout.write(str(i+1)+'\n')
            else:
                stdout.write('-1\n')
        else:
            b=int(b)-1
            o[b]=0
        q-=1
if __name__=='__main__':
    main()
'''
#82A
'''
def main():
    from sys import stdin, stdout
    n=int(stdin.readline())
    while n>5:
        if n&1:
            n-=5
            n//=2
        else:
            n-=4
            n//=2
    if n==1:
        stdout.write('Sheldon')
    elif n==2:
        stdout.write('Leonard')
    elif n==3:
        stdout.write('Penny')
    elif n==4:
        stdout.write('Rajesh')
    else:
        stdout.write('Howard')
if __name__=='__main__':
    main()
'''
#460A
'''
WA
def main():
    from sys import stdin,stdout
    n,m=map(int,stdin.readline().split())
    counter=n
    while n>=m:
        counter+=n//m
        n//=m
    stdout.write(str(counter))
if __name__=='__main__':
    main()
'''
#479A
'''
def main():
    from sys import stdin,stdout
    a=int(stdin.readline())
    b=int(stdin.readline())
    c=int(stdin.readline())
    maxim=a*b*c
    if a+b+c > maxim:
        maxim=a+b+c
    if (a+b)*c >maxim:
        maxim=(a+b)*c
    if a*(b+c)>maxim:
        maxim=a*(b+c)
    if a+b*c > maxim:
        maxim=a+b*c
    stdout.write(str(maxim))
if __name__=='__main__':
    main()
'''
#69A
'''
def main():
    from sys import stdin,stdout
    a,b,c=0,0,0
    for _ in range(int(stdin.readline())):
        x,y,z=map(int,stdin.readline().split())
        a+=x
        b+=y
        c+=z
    if a or b or c:
        stdout.write('NO')
    else:
        stdout.write('YES')
if __name__=='__main__':
    main()
'''
#580A
'''
def main():
    from sys import stdin,stdout
    n=int(stdin.readline())
    l=list(map(int,stdin.readline().split()))
    max_so_far=1
    counter=1
    for i in range(1,n):
        if l[i]>=l[i-1]:
            counter+=1
        else:
            max_so_far=max(max_so_far,counter)
            counter=1
    stdout.write(str(max(max_so_far,counter)))
if __name__=='__main__':
    main()
'''
#337A
'''
def main():
    from sys import stdin,stdout
    n,m=map(int,stdin.readline().split())
    li=sorted(list(map(int,stdin.readline().split())))
    minim=100000
    for i in range(m-n+1):
        sub=li[i:i+n]
        d=0
        for i in range(1,len(sub)):
            d+=sub[i]-sub[i-1]
        minim=min(minim,d)
    stdout.write(str(minim))
if __name__=='__main__':
    main()
'''
#472A
'''
def main():
    from sys import stdin,stdout
    from math import floor,sqrt
    def check(n):
        if n==2:
            return True
        elif n & 1:
            for i in range(3,floor(sqrt(n))+1):
                if n % i==0:
                    return False
            return True
        else:
            return False
    n=int(stdin.readline())
    i=4
    while True:
        #print(check(i),check(n-i))
        if check(n-i) or check(i):
            i+=1
            continue
        else:
            stdout.write(str(i)+' '+str(n-i))
            break
if __name__=='__main__':
    main()
'''
#119A
'''
def main():
    def gcd(a,b):
        if b:
            return gcd(b,a%b)
        else:
            return a
    from sys import stdin,stdout
    a,b,n=map(int,stdin.readline().split())
    flag=0
    while n > 0:
        if flag:
            n-=gcd(n,b)
            flag=0
        else:
            n-=gcd(n,a)
            flag=1
    if flag:
        stdout.write('0')
    else:
        stdout.write('1')
if __name__=='__main__':
    main()
'''
#451A
'''
def main():
    from sys import stdin,stdout
    a,b=map(int,stdin.readline().split())
    if a==1 or b==1:
        stdout.write('Akshat')
    elif min(a,b)**2 & 1:
        stdout.write('Akshat')
    else:
        stdout.write('Malvika')
if __name__=='__main__':
    main()
'''
#379A
'''
def main():
    from sys import stdin,stdout
    a,b=map(int,stdin.readline().split())
    counter=a
    while a:
        counter+=a//b
        if a > b:
            d=a%b
        else:
            d=0
        a=(a+d)//b
    stdout.write(str(counter))
if __name__=='__main__':
    main()
'''
#208A
'''
def main():
    from sys import stdin,stdout
    s=stdin.readline().strip()
    stdout.write(s.replace('WUB',' ').strip())
if __name__=='__main__':
    main()
'''
#144A
'''
def main():
    from sys import stdin,stdout
    n=int(stdin.readline())
    t=tuple(map(int,stdin.readline().split()))
    maxim=t[0]
    imaxim=0
    minim=t[0]
    iminim=0
    for i in range(1,n):
        if t[i] > maxim:
            maxim=t[i]
            imaxim=i
        if t[i] <=minim:
            minim=t[i]
            iminim=i
    if imaxim > iminim:
        stdout.write(str(imaxim+n-iminim-2))
    else:
        stdout.write(str(imaxim+n-iminim-1))
if __name__=='__main__':
    main()
'''
#469A
'''
def main():
    from sys import stdin,stdout
    a=set()
    n=set(range(1,int(stdin.readline())+1))
    for i in range(2):
        a.update(tuple(map(int,stdin.readline().split()))[1:])
    if a==n:
        stdout.write('I become the guy.')
    else:
        stdout.write('Oh, my keyboard!')
if __name__=='__main__':
    main()
'''
#344A
'''
def main():
    from sys import stdin,stdout
    state=''
    counter=0
    for _ in range(int(stdin.readline())):
        s=stdin.readline()
        if s!=state:
            counter+=1
            state=s
    stdout.write(str(counter))
if __name__=='__main__':
    main()
'''
#443A
'''
def main():
    from sys import stdin,stdout
    s=set(stdin.readline().strip()[1:-1].split(', '))
    if '' in s:
        stdout.write('0')
    else:
        stdout.write(str(len(s)))
if __name__=='__main__':
    main()
'''
#228A
def main():
    from sys import stdin,stdout
    stdout.write(str(4-len(set(map(int,stdin.readline().split())))))
if __name__=='__main__':
    main()
