#include<iostream>
#include<cmath>

using namespace std;

int ite_factorial(int n);
int rec_factorial(int n);
int perm_i(int n, int k);
int perm_r(int n, int k);

int main()
{
int n,k;

cout <<"Enter number of k items : ";
cin >> k;
cout << "Enter numbers in the set (n) : ";
cin >> n;

cout <<"Permutation calculated using iterative factorial function : " << perm_i << endl;
cout <<"Permutation calculated using recursive factorial function : " << perm_r << endl;


return 0;
}

int ite_factorial(int n)
{
int accu = 1;
int i;
for(i = 1; i <= n; i++) {
accu *= i;
}
return accu;
}


int rec_factorial(int n)
{
if( n == 1)
return 1;
else
{
return (n * (rec_factorial(n-1)));
}
}

int perm_i(int n, int k)
{
int P;
while(n >= 0)
{
P = ite_factorial(n)/ite_factorial(n-k);

}

return P;
}
int perm_r(int n, int k)
{
int P;
while(n >= 0)
{
P = rec_factorial(n)/rec_factorial(n-k);

}

return P;
}

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