// Online C++ compiler to run C++ program online
#include <iostream>
#include <string>
using namespace std;
/*int main() {
    
    cout<<"Starting...";
    try
    {
        int i = 0;
        cout<<endl<<"In try block";
        if(!i)
            throw 100;
        else throw "Hello";
    }
    
    catch(int i)
    {
        cout<<endl<<"caught exception with value: "<<i<<endl;
    }
    
    return 0;
}*/

//Program 2 using exceptions in Functions

void exhandle(int t)
{
    try
    {
        if(t) 
            throw t;
    }
    
    catch(int i)
    {
        cout<<endl<<"Exception Caught "<<i;
    }
}

/*int main()
{
    cout<<endl<<"Starting....";
    exhandle(1);
    exhandle(0);
    exhandle(3);
    exhandle(4);
    exhandle(5);
    
    cout<<endl<<"Over...";
    return 0;
}*/

// Catching class data type
class MyException
{
    public:
    string s;
    int q;
    
    MyException()
    {
        // *s = 0;
        q = 0;
    }
    
    MyException(string s1, int e)
    {
        s = s1;
        q = e;
    }
    
};

int main()
{
    int i;
    try
    {
        cout<<endl<<"Enter a Positive Number: ";
        cin>>i;
        
        if(!i) 
        {
            throw MyException("Not Positive ",i);
        }
        
    }
    
    catch(MyException E)
        {
            cout<<endl<<E.s<<" : "<<E.q;
        }
    
    
    return 0;
}

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}