How use #include <set>

Question

help me to use set library in cpp with examples plz
for instance, u have add many number of students with student id and students cannot enter same id(validation)

plz help me validation of set library

Answer 1

Set uses std namespace
insert(key) to add in new elements.
find(key) returns iterator to the key or end() iterator if key wasn't found.
Describe what you want to do so I can explain in more detail.