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  1. #include <stdio.h>
  2. int c = 0;
  3.  
  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. int main(void) {
  16.     int n;
  17.     scanf("%d", &n);
  18.     int result = rec(n);
  19.     printf("数列a%dの値は%d\n", n, result);
  20.     printf("このときrecの呼び出し回数は%d\n", c);
  21.  
  22.     return 0;
  23. }
  24.  
Success #stdin #stdout 0s 5312KB
comments (?)
stdin 
5
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/Z4PtkJ
language:
C (gcc 8.3)
created:
4 days ago
visibility:
public

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