Question

Recursive strategy in C

// gcc factorial.c -o factorial

// ./factorial

#include <stdio.h>

// TODO: Implement iterative solution here

int factorial(int n){

return 0;

};

// TODO: Implement recursive solution here

int factorial_rec(int n){

return 0;

}

int main(){

printf("factorial(10) = %d\n",factorial(10));

printf("factorial_rec(10) = %d\n",factorial_rec(10));

Once you have solved the above, answer and modify your programs for the following.

1. What is a bigger data type you can use to compute larger factorials? Change the 'return type' and input parameters to the factorial to something other than 'int' (and also change the format specifier in printf to something other than %d for the datatype you choose).

2. Try computing factorials larger than say 15. At what point does your computer start to 'crash' or really slow down when you try a big enough factorial? Experiment and report your results.

Answer 1

CODE IN C:

#include <stdio.h>

int factorial(int n){
if(n==0)
return 1;
int i , prod = 1;
for(i=1;i<=n;i++){
prod *= i ;
}

return prod;

}

int factorial_rec(int n){
if (n==0 || n==1)
return 1;
return n * factorial_rec(n-1);
}

int main()
{
printf("factorial(10) = %d\n",factorial(10));

printf("factorial_rec(10) = %d\n",factorial_rec(10));

return 0;
}

OUTPUT: