#include <stdio.h> int fun(int n){    if (n == 4)       return n;    else return 2*fun(n+1);}  int main(){   printf("%d", fun(2));   return 0;}4816Runtime Error

It seems like you're trying to run a recursive function in C, but you're encountering a runtime error. Here's a step-by-step explanation of your code:

1. You've defined a function fun(int n) that takes an integer n as an argument.
2. Inside this function, you've set a base case for the recursion: if n equals 4, the function returns n.
3. If n does not equal 4, the function calls itself with the argument n+1, multiplies the result by 2, and returns this value.
4. In your main function, you're calling fun(2) and printing the result.

The problem with your code is that you're not handling the case where n is greater than 4. This means that if n is greater than 4, your function will keep calling itself indefinitely, leading to a stack overflow and a runtime error.

To fix this, you need to add a condition to handle the case where n is greater than 4. Here's an example of how you could do this:

#include <stdio.h>

int fun(int n) {
    if (n == 4)
        return n;
    else if (n > 4)
        return 0; // or whatever value you want to return when n is greater than 4
    else
        return 2*fun(n+1);
}

int main() {
    printf("%d", fun(2));
    return 0;
}

This code will now return a value when n is greater than 4, preventing the stack overflow and runtime error.