How to iterate a list of vector
If I have a vector of object vector, how can I check if A* myA is inside that 开发者_C百科vector?
Try this...
#include <algorithm>
bool in_vector(const std::vector<A*>& vec, const A* myA)
{
std::vector<A*>::const_iterator end = vec.end();
return std::find(vec.begin(), end, myA) != end;
}
This might or might not work:
vector<int> v;
. . .
for (int i=0; i<v.size(); i++) {
//---do a compare of v[i] with your object?
cout << v[i] << endl;
}
Perhaps something like this:
std::vector<A*> v;
for (std::vector<A*>::iterator it = v.begin(); it != v.end(); ++it) {
// Do comparison with *it to your myA...
}
This is an expansion of wowus' answer for what I think is closer to what you want to do:
#include <algorithm>
// let's call it simply TVectorVectorA and TVectorA
typedef std::vector<std::vector<A*> > TVectorVectorA;
typedef TVectorVectorA::value_type TVectorA;
bool in_vector(const std::vector<std::vector<A*> >& vec, const A* myA)
{
TVectorVectorA::const_iterator vend = vec.end();
// iterate through all 'top-level' vectors
for (TVectorVectorA::const_iterator it = vec.begin(); vend != it; ++it)
{
// check if the current TVector element contains myA
if (std::find((*it).begin(), (*it).end(), myA) != end)
{
return true;
}
}
return false;
}
It's always nice to give a relevant code example (i.e. declaration of data types you're working with), when asking such questions. This way it's easier for others to understand what you want to do.
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