I have the following structs:
enum messageType {New = 0, Old = 1, No_Message = 2};
typedef struct {
enum messageType type;
unsigned int senderID;
char message[100];
} StoredMessageData;
struct StoredMessage {
unsigned int recipientID;
vector<StoredMessageData> messages;
StoredMessage(const unsigned int& intRecipient = 0, const vector<StoredMessageData>& data = vector<StoredMessageData>())
: recipientID(intRecipient), messages(data)
{
messages.reserve(10);
}
bool operator<(const StoredMessage& compareTo) const
{
return recipientID < compareTo.recipientID;
}
bool operator==(const StoredMessage& compareTo) const
{
return recipientID == compareTo.recipientID;
}
};
In my main method, at some point I receive a message and want to store it like so:
if(msgs.find(rcvdRecipientID) == msgs.end())
{
StoredMessage storedMsg;
storedMsg.recipientID = rcvdRecipientID;
msgs.insert(storedMsg);
}
set<StoredMessage>::iterator it = msgs.find(rcvdRecipientID);
StoredMessage storedMsg = *it;
StoredMessageData data;
data.type = New;
data.senderID = rcvdSenderID;
strcpy(data.message, rcvdMessage);
storedMsg.messages.push_back(data);
If, after push_back(), I call storedMsg.messages.size(), I am given a value of 1. This makes sense to me.
However, later, I wish to know how many messages I stored, so, this code:
StoredMessage storedMsg;
if(msgs.find(rcvdSenderID) != msgs.end())
{
storedMsg = *(msgs.find(rcvdSenderID));
cout << "Number of stored messages to send: " << int(storedMsg.messages.size()) << endl << endl;
...
Here, storedMsg.messages.size() returns 0 even when the same ID as before is used... I am confused as to why this is happening and suspect it has to do with the vectors being copied as their size varies, but I'm not sure. I am not a C++ expert, so please be gentle. Thank you!
Propbably it happens because here
StoredMessage storedMsg = *it;
You create the copy of object and do all the modifications to the copy.
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