Define Constant argument:
The argument can be a constant argument. The constant variable cannot be changed inside the function definition when the argument is declared as constant.
void f_const(int x, const int y);
void main( )
{int a10, b=20,c;
c =f_const(a, b); //The value of c is 30
}
int f_ref(int x, const int y)
{ //y=20; // Is invalid because y is declared as constant variable. return (x+y);
}
void f_const(int x, const int y=100);
void main( )
{int a=200, b,c;
c =f_const(a); //The value of c is 300
}
int f_const(int x, const int y)
{ //y=20; // Is invalid because y is declared as constant variable. return (x+y);
}