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  1. #include <stdio.h>
  2. int c = 0;
  3. int rec(int n) {
  4.     c++;
  5.  
  6.     if (n == 1) {
  7.         return 1;
  8.     }
  9.     else if (n == 2) {
  10.         return 2;
  11.     }
  12.     else {
  13.         return -6 * rec(n - 1) - 9 * rec(n - 2);
  14.     }
  15. }
  16.  
  17. int main(void) {
  18.     int n = 5;
  19.     printf("数列a%dの値は%d\n", n, rec(n));
  20.     printf("このときrecの呼び出し回数は%d\n", c);
  21.     return 0;
  22. }
  23.  
Success #stdin #stdout 0.01s 5288KB
comments (?)
stdin 
Standard input is empty
stdout 
数列a5の値は-459
このときrecの呼び出し回数は9
https://ideone.com/KN0nVL
language:
C (gcc 8.3)
created:
1 day ago
visibility:
public

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