I’d like to do it all by myself.. You should only compare the values of Obj::field2 if the values of Obj::field1 are equal. The easy-to-understand way: /* This will meet the requirements of Strict-Weak-Ordering */ if (a.field1 != b.field1) return a.field1 < b.field1; else return a.field2 < b.field2; The correct (recommended) way: The “correct” way … Read more
Sometimes you want it to be >>. Consider boost::array<int, 1024>>2> x; In C++03 this successfully parses and creates an array of size 256.
Leading from answers from @Bozho and @aioobe, lexicographic comparisons are similar to the ordering that one might find in a dictionary. The Java String class provides the .compareTo () method in order to lexicographically compare Strings. It is used like this “apple”.compareTo (“banana”). The return of this method is an int which can be interpreted … Read more
Let’s look at some permutations: 1 2 3 4 1 2 4 3 1 3 2 4 1 3 4 2 1 4 2 3 1 4 3 2 2 1 3 4 … How do we go from one permutation to the next? Firstly, let’s look at things a little differently. We can view … Read more
lexicographical order is alphabetical order. The other type is numerical ordering. Consider the following values, 1, 10, 2 Those values are in lexicographical order. 10 comes after 2 in numerical order, but 10 comes before 2 in “alphabetical” order.