1

def f(a,b,c,n=0,a1=0,b1=0,c1=0):
    if a*a1+b*b1+c*c1==1000:
        n+=1
    c1+=1
    if c1 == 1000//c:
        b1 += 1
        c1 = 0
        if b1 == 1000//b:
            b1 = 0
            a1 += 1
            if a1== 1000//a:
                return n
    return f(a,b,c,a1=a1,b1=b1,n = n)