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  1. #include <stdio.h>
  2. //a{n} = -6a{n-1} -9a{n-2}, a{1}=1, a{2}=2(再帰あり版)
  3. int c;
  4. int rec(int n){
  5. 	c++;
  6. 	if(n==1){
  7. 		return 1;
  8. 	}else if(n==2){
  9. 		return 2;
  10. 	}else{
  11. 		return -6*rec(n-1)-9*rec(n-2);
  12. 	}
  13.  
  14. }
  15.  
  16. int main(void) {
  17.     int n = 4 ;
  18.     printf("数列a%dの値は%d\n", n, rec(n));
  19.     printf("このときrecの呼び出し回数は%d",c);
  20. 	return 0;
  21. }
  22.  
  23.  
Success #stdin #stdout 0.01s 5276KB
comments (?)
stdin 
5
stdout 
数列a4の値は108
このときrecの呼び出し回数は5
https://ideone.com/2b0lw4
language:
C (gcc 8.3)
created:
72 days ago
visibility:
public

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