fork download
copy 
  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){
  8.     	return 1;
  9.     }
  10.     else if(n==2){
  11.     	return 2;
  12.     }
  13. 	else{
  14. 		for(i=3;i<=n;i++){
  15. 			a=-2*b+2*c;
  16. 			c=b;
  17. 			b=a;
  18. 		}
  19. 		return a;
  20. 	}
  21.  
  22. }
  23. int main(void) {
  24. 	int n = 3;
  25.     printf("数列anについて, n=%dのときの値は%d\n", n, func(n));
  26. 	return 0;
  27. }
  28.  
Success #stdin #stdout 0.01s 5288KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
数列anについて, n=3のときの値は-2
https://ideone.com/xE1fpI
language:
C (gcc 8.3)
created:
8 days 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!