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  1. #include <stdio.h>
  2.  
  3. int c = 0;
  4.  
  5. int rec(int n) {
  6.     c++;
  7.  
  8.     if (n == 1) {
  9.         return 1;
  10.     } else if (n == 2) {
  11.         return 2;
  12.     } else {
  13.         return -6 * rec(n - 1) - 9 * rec(n - 2);
  14.     }
  15. }
  16.  
  17. int main(void) {
  18.     int n;
  19.  
  20.     scanf("%d",&n);
  21.  
  22.     int ans = rec(n);
  23.  
  24.     printf("数列a%dの値は%d\n", n, ans);
  25.     printf("このときrecの呼び出し回数は%d\n", c);
  26.  
  27.     return 0;
  28. }
  29.  
  30.  
Success #stdin #stdout 0s 5320KB
comments (?)
stdin
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5
stdout
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数列a5の値は-459
このときrecの呼び出し回数は9
https://ideone.com/wFJZ3a
language:
C (gcc 8.3)
created:
18 hours ago
visibility:
public

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