Lists inside dictionary and how to look for particular value

[Peter Otten]

mick verdu wrote:

> z={ 'PC2': ['02:02:02:02:02:02', '192.168.0.2', '200'],
>     'PC3': ['03:03:03:03:03:03', '192.168.0.3', '200'],
>     'PC1': ['01:01:01:01:01:01', '192.168.0.1', '200'] }
> 
> My solution:
> 
> z=raw_input("Enter Host, Mac, ip and time")
> t=z.split()
> t[0]=z[1:]
> for key in dic:
>     if t[2] in dic[key]:
>         del dic[t[0]]
>     else:
>         dic[t[0]] = t[1:]
> 
> 
> What I really want to achieve is:
> 
> 
> How to search for a particular value inside list. First, I want the user
> to input hostname and ip. e.g. PC1 and 192.168.0.1, then need to find out
> if 192.168.0.1 has already been assigned to some host in dictionary. In
> this case I would need to skip for search inside list of user input host.
> 
> Forexample, if user inputs PC1 and 192.168.0.1 i would like to skip
> searching in above PC1's values. So it should detect matching only with
> different hosts and skip its own name.
> 
> If i input PC4 and 192.168.0.1 then it should detect conflict with PC1. So
> PC4 would be deleted(As soon as user inputs new host it is saved in above
> database then if conflict with others deleted)

You are making the problem unnecessarily complex. For the example scenario 
start with a dict that maps host to ip:

host2ip = {
 "PC1": "192.168.0.1",
 "PC2": "192.168.0.2",
 "PC3": "192.168.0.3",
}

host, ip = raw_input("Enter host and ip: ").split()
if host not in host2ip:
    print "adding", host
    host2ip[host] = ip
else:
    old_ip = host2ip[host]
    if old_ip == ip:
        print "no changes necessary"
    else:
        print "updating ip for", host, "from", old_ip, "to", ip
        host2ip[host] = ip


Then proceed and come up with an unambiguous description of what to do with 
mac and time in plain english, and add or modify data structures as 
necessary.