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  1. #include <stdio.h>
  2. //練習問題G
  3.  
  4. int func(int n){
  5.     int a, b=2, c=1;
  6.     int i;
  7.     if (n == 1) return 1;
  8.     if (n == 2) return 2;
  9.  
  10.     for (i = 3; i <= n; i++) {
  11.         a = 2 * c - 2 * b;
  12.         c = b;
  13.         b = a;
  14.     }
  15.  
  16.     return b;
  17. }
  18.  
  19.  
  20. int main(void) {
  21. 	int n = 3;
  22.     printf("数列anについて, n=%dのときの値は%d\n", n, func(n));
  23. 	return 0;
  24. }
  25.  
Success #stdin #stdout 0s 5320KB
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Standard input is empty
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数列anについて, n=3のときの値は-2
https://ideone.com/Dknt4Y
language:
C (gcc 8.3)
created:
1 day ago
visibility:
public

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