set in cpp

1#include <bits/stdc++.h>
2#include <iostream>
3#include <vector>
4#include <algorithm>
5#include <set>
6
7using namespace std;
8//set mentains internally the ascending order of these numbers
9void setDemo()
10{
11	set<int> S;
12	S.insert(1);
13	S.insert(2);
14	S.insert(-1);
15	S.insert(-10);
16	S.erase(1);//to remove an element
17	
18	//Print all the values of the set in ascending order
19	for(int x:S){
20		cout<<x<<" ";
21	}
22	
23	//check whether an element is present in a set or not
24	auto it = S.find(-1);//this will return an iterator to -1
25	//if not present it will return an iterator to S.end()
26	
27	if (it == S.end()){
28		cout<<"not Present\n";
29	}else{
30		cout <<" present\n";
31		cout << *it <<endl;
32	}
33	//iterator to the first element in the set which is
34	//greater than or equal to -1
35	auto it2 = S.lower_bound(-1);
36	//for strictly greater than -1
37	auto it3 = S.upper_bound(-1);
38	//print the contents of both the iterators
39	cout<<*it2<<" "<<*it3<<endl;
40}
41	
42int main() {
43	setDemo();
44	return 0;
45}

1#include<iostream>
2#include<set>
3 
4using namespace std;
5 
6int main(){
7 
8    // Set with values
9    set<int, greater<int>> s1 = {6, 10, 5, 1};
10    // s1 = {10, 6, 5, 1}
11 
12    // Inserting elements in the set
13    s1.insert(12);
14    s1.insert(20);
15    s1.insert(3);
16 
17    // Iterator for the set
18    set<int> :: iterator it;
19 
20    // Print the elements of the set
21    for(it=s1.begin(); it != s1.end();it++)
22        cout<<*it<<" ";
23    cout<<endl;
24 
25}

1#include<iostream>
2#include<set>
3 
4using namespace std;
5 
6int main(){
7 
8    // Set with values
9    set<int, greater<int>> s1 = {6, 10, 5, 1};
10     
11    // Iterator for the set
12    set<int> :: iterator it;
13 
14    // Print the elements of the set
15    for(it=s1.begin(); it != s1.end();it++)
16        cout<<*it<<" ";
17    cout<<endl;
18}

1// constructing sets
2#include <iostream>
3#include <set>
4
5bool fncomp (int lhs, int rhs) {return lhs<rhs;}
6
7struct classcomp {
8  bool operator() (const int& lhs, const int& rhs) const
9  {return lhs<rhs;}
10};
11
12int main ()
13{
14  std::set<int> first;                           // empty set of ints
15
16  int myints[]= {10,20,30,40,50};
17  std::set<int> second (myints,myints+5);        // range
18
19  std::set<int> third (second);                  // a copy of second
20
21  std::set<int> fourth (second.begin(), second.end());  // iterator ctor.
22
23  std::set<int,classcomp> fifth;                 // class as Compare
24
25  bool(*fn_pt)(int,int) = fncomp;
26  std::set<int,bool(*)(int,int)> sixth (fn_pt);  // function pointer as Compare
27
28  return 0;
29}