STL List Sorting

[LB]

That won't let you sort by a different value.

You need to use a lambda or a functor like in my original example, except instead of std::sort you use transaction.sort.
http://www.cplusplus.com/reference/list/list/sort/

struct TransactionPriceComparator
{
    bool operator()(const WHMgmtDetails &a, const WHMgmtDetails &b)
    {
        return a.unitPrice < b.unitPrice;
    }
};

transaction.sort(TransactionPriceComparator());

struct TransactionQuantityComparator
{
    bool operator()(const WHMgmtDetails &a, const WHMgmtDetails &b)
    {
        return a.qty < b.qty;
    }
};

transaction.sort(TransactionQuantityComparator());

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