1. C is a procedure or function oriented language whereas C++ is a Object oriented language.
2. C has top down approach whereas C++ has a bottom up approach.
3. In C++ new and delete operators are used to allocate and free memory but in C malloc() and free() functions are used for allocation and freeing memory.
4. In C++ prototype of a function have to be defined before using it but in C functions can be used without defining a prototype.
5. Structures of C++ can have functions in them but C structures can only have variables.
6. For I/O C++ has iostream.h and C has stdio.h.
7. Function overloading is allowed in C++ but functions in C does not support overloading.
8. In C we have to include the struct keyword before the name of the structure to declare a instance of a structure. In C++ only the structure name is required. Example - :
struct employee
{
int id;
char *name;
// other variables
};
//Statement to declare structure variable in C
struct employee e1;
//Statement to declare structure variable in C++
employee e1;
main() doesn’t add return 0 statement automatically in C. In C++ it provide this statement.
//In C++ return 0 is added automatically.
int main()
{
printf(“Hello How are you”);
}
//In C return 0 has to be added manually.
int main()
{
printf(“Hello How are you”);
return 0;
}
9. C allows a void* pointer to be assigned to any pointer type without a cast, whereas C++ does not
10. Enumeration constants are always of type int in C, whereas they are distinct types in C++ and may have size different from that of int.
11.C++ identifiers are not allowed to contain two or more consecutive underscores in any position. C identifiers are not allowed to start with two or more consecutive underscores, but may contain them in other positions
12. C allows struct, union, and enum types to be declared in function prototypes, whereas C++ does not.