java programming Write program to find factorial of a number

java programming

Write program to find factorial of a number n using itrativ approach. What is the time and space compexity? Now write the recurive version. What is the time and space compexity?

Solution

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package chegg;

public class TestFactorial {

/*
Space Complexity : O(1)
Time Complexity : O(n)
*/
public static int factIter(int n)
{
int fact = 1;
int i=1;
while(i<=n)
{
fact = fact*i;
i++;
}
  
return fact;
}
  
/*
Space Complexity = O(n) since n calls will be present at max in rec stack
*/
public static int factRec(int n)
{
if(n==0 || n==1)
return 1;
else
return n*factRec(n-1);
}
  
public static void main(String[] args)
{
System.out.println(\"Factorial of 5 is : \"+factRec(5));
System.out.println(\"Factorial of 5 is : \"+factIter(5));
}
  
}