fork download 
  1. #include <stdio.h>
  2. //a{n} = -6a{n-1} -9a{n-2}, a{1}=1, a{2}=2(再帰なし版)
  3.  
  4. int main(void) {
  5.     int n = 1;
  6.     int a, b = 2, c = 1; 
  7.     if(n==1){
  8.     	a=1;
  9.     }
  10.     else if(n==2){
  11.     	a=2;
  12.     }
  13.     else{
  14.     for(int i = 3; i <= n; i++){
  15.         a = -6*b -9*c;
  16.         c = b;
  17.         b = a;
  18.     }
  19.     }
  20.     printf("数列a%dの値は%d\n", n, a);
  21. 	return 0;
  22. }
  23.  
  24.  
Success #stdin #stdout 0.01s 5284KB
comments (?)
stdin 
Standard input is empty
stdout 
数列a1の値は1
https://ideone.com/J5Y4h0
language:
C (gcc 8.3)
created:
1 day ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!