Sets are containers that store unique elements following a specific order. Internally, the elements in a set are always sorted. Sets are typically implemented as binary search trees.
set::size()
size() function is used to return the size of the set container or the number of elements in the set container.
Syntax:
set_name.size()
Return Value: It returns the number of elements in the set container.
Examples:
Input : set1{'a', 'b', 'c', 'd'};
set1.size();
Output : 4
Input : set2{};
set2.size();
Output : 0
Errors and Exceptions
1. It has a no exception throw guarantee.
2. Shows error when a parameter is passed.
// C++ program to illustrate // size() function on set #include <bits/stdc++.h> using namespace std; int main() { // Take any two sets set<char> set1, set2; for (int i = 0; i < 4; i++) { set1.insert('a' + i); } // Printing the size of sets cout << "set1 size: " << set1.size(); cout << endl; cout << "set2 size: " << set2.size(); return 0; } |
Output:
set1 size: 4 set2 size: 0
Time complexity: Constant
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