Question

Please solve the program in C++(Recursive)

Write a function called factorialIterative(). This function should take a single BIG integer (bigint) as its parameter n, and it will compute the factorial n! of the value and return it as its result (as a bigint). Write this functions using a loop (do not use recursion). 2. Write the factorial function again, but using recursion. Call this function factorialRecursive(). The function takes the same parameters and returns the same result as described in 1. 3. Write a function called countCombinationsDirectly(). This function will compute the number of combinations that result from choosing i elements from set of n items. The function should take two bigint values as its parameters n and i, which will be integers >= 0. The function should use the equation 3 above to directly compute the number of combinations. You should use your factorialRecursive() function to compute the factorials in this function. 4. Write a function called countCombinationsRecursive(). This function will also count the number of combinations of choosing i elements from a set of n items. However, you need to implement this calculation as a recursive function, using the general and base cases described above for counting combinations in equation 4 (general case) and equation 5 (base cases). Your function will take the same two bigint parameters as input n and i with values >= 0, and will return a bigint result. 3

Answer 1

1)

int factorialIterative(long n)
{
int i,f=1;
for(i=1;i<=n;i++)
f=f*i;
return(f);
}

2)

unsigned long factorialRecursive(int n)

{

if(n > 1)

return n * factorialRecursive(n - 1);

else

return 1;

}

3)

int fact(int no)
{
int i,f=1;
for(i=1;i<=no;i++)
f=f*i;
return(f);
}

int nCr(int n, int r)

{

    return fact(n) / (fact(r) * fact(n - r));

}

4)

int fact(int n);

  

int nCr(int n, int r)

{

    return fact(n) / (fact(r) * fact(n - r));

}

  

// Returns factorial of n

int fact(int n)

{

    int res = 1;

    for (int i = 2; i <= n; i++)

        res = res * i;

    return res;

}