Rank: ? (6)
Member #: 29538

I want the following logic to be implemented in C++. It is similar to the concept of building a truth table.

The user will provide set of inputs and their states, say

In1 v11 v12
In2 v21 v22

where (v11 v12 and v21 v22) are the two inputs states. I need to create a flow which iterates through all possible permutations of these states.

Example

In1 In2
v11 v21
v11 v22
v12 v21
v12 v22 just like a truth table.

the user provides the input during the run.

Can someone please help me solve this.

Thanks.

Rank: ? (767)
Member #: 11085

You need to use a nested loop. For example:
Code:

Rank: ? (6)
Member #: 29538

that is true if i know the number of inputs(namely A and B) but what if i dont know the number of inputs.

Thanks.

Rank: ? (767)
Member #: 11085

You use an iterator and a vector instead of an integer and a static array.

Rank: ? (6)
Member #: 29538

Could you please demostrate that with an example. I am really not getting this concept. Thanks

Rank: ? (767)
Member #: 11085

Why didn't you originally just ask what an iterator was? That would have saved you some time. Anyway, I'll show you an example of how an iterator works.

Code:


vector<int>::iterator would be replaced with whatever type of vector you are using and the iterator is always a pointer to the current value, which is why it is dereferenced.

Rank: ? (6)
Member #: 29538

Thanks. I think i was not clear regarding the problem.

I need to generate all possible combinations between the inputs provided by the user. These inputs futher have 2 states each( 0 and 1). So if the user provides 2 inputs (A & B) then i need to generate the following combinations

A B
0 0
0 1
1 0
1 1

if the user provides 3 inputs ( A B C) then i need to generate

A B C
0 0 0
0 0 1
0 1 0
0 1 1
1 0 0
1 0 1
1 1 0
1 1 1


I know i need to use the iterator but i cannot get the flow algorithm properly. Hope this makes the problem a little clear.

Thanks.

Rank: ? (767)
Member #: 11085

If you have a variable amount of inputs with a variable amount date for each, use a vector of vectors for the input variables.

Why don't you show the code you have so far so I can tell you what you are doing wrong?

Rank: ? (6)
Member #: 29538

Thank You.

One more clarification. I want to get all possible combinations for given number of inputs and their respective values.

Example

Input Values
A1 V1 V2
B1 V3 V4

I want all the possible combinations (in this case they will be 4), namely

V1 V3
V1 V4
V2 V3
V2 V4.

I am using map<string, vector<string>> to store the pins and their values but I am not getting the logic to find all possible combinations.
Please suggest.

Thanks,

Rank: ? (767)
Member #: 11085

I already have suggested it, multiple times. Run an iterator through your map and then, inside that iterator, run an iterator through the vector portion of the map.

Rank: ? (6)
Member #: 29538

map<string, vector<string>> state;
map<string, vector<string>> ::iterator mi;
vector<string>:: iterator vi;

for(mi = state.begin(); mi != state.end(); mi++){
for(vi = mi.begin(); vi != mi.end(); vi++){
(*mi).first = (*mi).second[*vi];

// This should assign the first string member a value from vector<string>

Is this correct?
}
}

thanks.

Rank: ? (767)
Member #: 11085

If you are still trying to do what you stated in your original post, read in a variable amount of inputs with a variable amount of data and print out all possible combinations, then no. You don't even have a command in that code to print, however, so I am not certain you are attempting that any longer.

Nonetheless, at present, if that code could compile, it would do no more than than set the string of each member in state equal to the string of the final value in the vector portion of state.

In any case, would you please clarify if you are still trying to do what you originally posted? If so, and that is your code at present, not to be rude, but you should consider telling the truth in the future and not say you are having trouble figuring out the logic behind a problem but rather, that you have no idea how to program the solution to a problem in order that I or anyone else answering your question better knows how to respond.