C++ Revision Day-6

1) How to input string in C++?

There are three ways to input a string, using cin, get, and getline. All three methods are mentioned in the sample program below.

#include <iostream>
using namespace std;

int main()
{
    char s[10];

    cout << "Enter a string: ";
    cin >> str;

    cout << "nEnter another string: ";
    cin.get(s, 10);

    getline(cin, str);

    return 0;
}

Summary of Differences:

• cin: Reads formatted input, skips leading whitespace, stops at first whitespace after the input.

• cin.get(): Reads a single character, including whitespace.

• getline(): Reads an entire line of text, including spaces, and stops at the newline character.

2) How to get absolute value in C++?

In C++, there are three functions in the cstdlib header file to return the absolute value of the integer. Those are:

• abs()

• labs()

• llabs()

• For abs() its type int in C++.

• For labs(), its type long int in C++

• For llabs() its long long int in C++.

3) Outputs:-

1.  // Assume that integers take 4 bytes. 
    #include<iostream> 
   
    using namespace std; 
   
    class Test 
    { 
    static int i; 
    int j; 
    }; 
   
    int Test::i; 
   
    int main() 
    { 
        cout << sizeof(Test); 
        return 0; 
    }
   

   output : 4
   static data members do not contribute in size of an object. So ‘i’ is not considered in size of Test. Also, all functions (static and non-static both) do not contribute in size.

2.  #include<iostream> 
   
    using namespace std; 
    class Base1 { 
    public: 
        Base1() 
        { cout << " Base1's constructor called" << endl; } 
    }; 
   
    class Base2 { 
    public: 
        Base2() 
        { cout << "Base2's constructor called" << endl; } 
    }; 
   
    class Derived: public Base1, public Base2 { 
    public: 
        Derived() 
        { cout << "Derived's constructor called" << endl; } 
    }; 
   
    int main() 
    { 
    Derived d; 
    return 0; 
    }