pointers in python code example

Example 1: pbds in c++

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;

typedef tree<int, null_type, less<int>, rb_tree_tag,
                    tree_order_statistics_node_update>
                    ordered_set;

ordered_set ord_set;

int a;
ord_set.insert(a);
*ord_set.find_by_order(a);
ord_set.order_of_key(a);

Example 2: floor() in c++

floor(x):This function in C++ returns the smallest possible integer value which is smaller
 than or equal to the given argument.
Input : 2.5 ,-2.1 ,2.9
Output : 2 ,-3, 2

Example 3: How to use pointers in C

myvar = 25;
foo = &myvar;
bar = myvar;

Example 4: fail() in c++

#include <iostream>
using namespace std;

int main()
{
    int number;
    do{
        cin >> number;
        if(cin.fail())
            cout << "Not a number " << endl;
    }while(!cin.fail());
    cout << "number is " << number << endl;
    system("pause");
    return 0;
}