Multimap iteration

Moderator: biskot188

Page 1 of 1

[ 2 posts ]

Author

Question

AskBot

Question subject: Multimap iteration

Posted: Fri Nov 07, 2008 6:15 pm

Joined: Sun Oct 19, 2008 3:47 pm
Posts: 281
Has thanked: 0 time
Have thanks: 1 time

Im currently working with multimap in C++. So for example i got a multimap like
this:

Code:

m.insert(pair<const char* const, int>("a", 1));
m.insert(pair<const char* const, int>("c", 2));
m.insert(pair<const char* const, int>("b", 3));
m.insert(pair<const char* const, int>("b", 4));
m.insert(pair<const char* const, int>("a", 5));
m.insert(pair<const char* const, int>("b", 6));

and i want to loop it but without repeating the same key eg: I want to print
average of each key and print like this

Code:

a = 3
b = 6.3
c = 2

My current solution is loop each key and find all other value with the same key.
So its like a loop in loop. But the problem is I print a twice, b three times,
and C once. How can I skip the repetition so it wont print the same key again?

AnswerBot

Question subject: Re: Multimap iteration

Posted: Fri Nov 07, 2008 6:17 pm

Joined: Sun Oct 19, 2008 3:53 pm
Posts: 229
Has thanked: 0 time
Have thanks: 0 time

If there are no memory constraints you can create a temporary map of key
& valueInfo.
valueInfo can be a structure like following...

Code:

Struct valueInfo
{
int val_total;
int count
}

Now you can fill this map while traversing your original data structure
(multimap) ...

For your example it will be

Code:

("a", (6,2))
("b", (13,3))
("c", (2,1))

Once you have traversed the original data structure, you can calculate
the desired output with a single traversal of your temp map.

So it will be Loop after Loop solution instead of yours Loop in Loop

Page 1 of 1

[ 2 posts ]

Codemiles.com » Programming Forums » C-C++

All times are UTC [ DST ]

Users browsing similar posts

Users browsing this forum: No registered users and 3 guests

Jump to:

Previous Question | Next Question