import sys
input=sys.stdin.readline
def I(): return int(input())
def MI(): return map(int, input().split())
def LI(): return list(map(int, input().split()))

def main():
    mod=10**9+7
    p,q,r=MI()
    
    aaa=[p,q,r]
    for i in range(3):
        aaa[i]/=(p+q+r)
        
    ans=0
    for i in range(3):
        ans=max(ans,aaa[i],1-aaa[i])
    print(ans)
        
    


main()