简单的递归问题

Question

This code gives every step-result of computing factorial of given number but I want only the final.

#include <stdio.h>

long int factorial(int n) {
  if (n <= 1)
    return(1);
  else
    n = n * factorial(n - 1);
  printf("%d\n", n);
  return(n);
}

main() {
  int n;
  printf("Enter n: ");
  scanf("%d", &n);

  //function call
  factorial(n);
  return 0;
}

Answer 1

How about this?

int final;

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

And stop using printf in the factorial function.

Answer 2

So don't use printf inside your recursive function but only print the return value inside main() .

Answer 3

Avoid using printf(); in the recursive function.

Writing printf(); inside the recursive function is printing the value everytime. So, just place it outside the function.

Like this:

#include <stdio.h>

long int factorial(int n) {
    if (n<=1)
        return(1);
    else
        n=n*factorial(n-1);
    return(n);
}

main() {
    int n,f;
    printf("Enter n: ");
    scanf("%d",&n);
    //function call
    f = factorial(n);
    printf("Factorial of %d is %d\n",n,f);     // See the change here ....
    return 0;
}

Answer 4

long int factorial(int n){
     if(n<=1)
        return 1;
     return n*factorial(n-1);
}

Answer 5

Use this,

long int factorial(int n) {    
    if (n<=1)      
        return(1);  
    else    
        n=n*factorial(n-1);  
    //printf("%d\n",n);    
    return(n);
} 

main(){ 
    int n, result;  
    printf("Enter n: ");  
    scanf("%d",&n);
    //function call  
    result=factorial(n);
    printf("%d\n",result);    

    return 0;
}

Answer 6

_{[This answer was originally edited into the question by the original poster, replacing the incorrect code. The question has been restored and the solution re-posted in this community wiki answer.]}

---

Reworked the code and now it looks like this. Thanks for the suggestions.

#include <stdio.h>
long int factorial(int n)
{
    if (n<=1)
        return(1);
    else
        n=n*factorial(n-1);
    return(n);
}
int final(int n)
{
    int result = factorial(n);
    printf("%d! = %d\n", n, result);
    return 0;
}

main()
{
    int n;
    printf("Enter n: ");
    scanf("%d",&n);
    //function call
    final(n);
    return 0;
}