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  1. #include <stdio.h>
  2.  
  3. int fn(int n)
  4. {
  5. 	if(n==1)
  6. 		return 1;
  7. 	else
  8. 		return 2 * fn(n-1) + 1;
  9. }
  10.  
  11. int main(void)
  12. {
  13. 	int a;
  14.  
  15. 	scanf("%d",&a);
  16. 	printf("%d\n",fn(a));
  17.  
  18. 	return 0;
  19. }
Success #stdin #stdout 0.01s 5320KB
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https://ideone.com/AH6c3T
[再帰] 2fn+1
language:
C (gcc 8.3)
created:
1 day ago
visibility:
public

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