interval_map<K,V> is a data structure that efficiently associates intervals of keys of type K with values of type V. Your task is to implement the assign member function of this data structure, which is outlined below.
interval_map<K, V> is implemented on top of std::map. In case you are not entirely sure which functions std::map provides, what they do and which guarantees they provide, we provide an excerpt of the C++ standard here:
Each key-value-pair (k,v) in the std::map means that the value v is associated with the interval from k (including) to the next key (excluding) in the std::map.
Example: the std::map (0,'A'), (3,'B'), (5,'A') represents the mapping
0 -> 'A' 1 -> 'A' 2 -> 'A' 3 -> 'B' 4 -> 'B' 5 -> 'A' 6 -> 'A' 7 -> 'A' ... all the way to numeric_limits::max() The representation in the std::map must be canonical, that is, consecutive map entries must not have the same value: ..., (0,'A'), (3,'A'), ... is not allowed. Initially, the whole range of K is associated with a given initial value, passed to the constructor of the interval_map<K,V> data structure.