Pass pointer to const int in recursive call


Neeraj Bansal

How to pass pointers const intin recursive calls . I'm calculating Fibonacci recursively using the following code format, but I'm getting an error:

error: lvalue must be unary '&' operand**

#include <iostream>

void fun(const int *n)
{    
    fun( &(*n-1) );   // it is giving error.
}
int main()
{
    const int n = 4;
    fun(&n);
}
Nasto

Then you would have to use another variable, and assign it a decremented const variable: you simply can't pass the decremented value of a const variable, because by definition it can't be modified by neither increment nor decrement.

#include <iostream>
void fun2 (const int *n)
{
    std::cout << *n << std::endl;
}
void fun1(const int *n)
{
    int x = *n-1;
    fun2( &x );
}
int main()
{
  const int n = 4;
  fun1(&n);
}

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Neeraj Bansal How to pass pointers const intin recursive calls . I'm calculating Fibonacci recursively using the following code format, but I'm getting an error: error: lvalue must be unary '&' operand** #include <iostream> void fun(const int *n) { fu

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Neeraj Bansal How to pass pointers const intin recursive calls . I'm calculating Fibonacci recursively using the following code format, but I'm getting an error: error: lvalue must be unary '&' operand** #include <iostream> void fun(const int *n) { fu

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