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  1. #include <stdio.h>
  2. int fib1(int n) {
  3.     if (n == 0) return 0;
  4.     if (n == 1) return 1;
  5.  
  6.     int a = 0, b = 1, fib;
  7.     for (int i = 2; i <= n; i++) {
  8.         fib = a + b;
  9.         a = b;
  10.         b = fib;
  11.     }
  12.     return fib;
  13. }
  14. int fib2(int n) {
  15.     if (n == 0) return 0;
  16.     int fib[n + 1];
  17.     fib[0] = 0;
  18.     fib[1] = 1;
  19.  
  20.     for (int i = 2; i <= n; i++) {
  21.         fib[i] = fib[i - 1] + fib[i - 2];
  22.     }
  23.     return fib[n];
  24. }
  25.  
  26. int fib3(int n) {
  27.     if (n == 0) return 0;
  28.     if (n == 1) return 1;
  29.     return fib3(n - 1) + fib3(n - 2);
  30. }
  31.  
  32. int main(void) {
  33.     int n;
  34.     scanf("%d", &n);
  35.  
  36.     printf("1: %d\n", fib1(n));
  37.     printf("2: %d\n", fib2(n));
  38.     printf("3: %d\n", fib3(n));
  39.  
  40.     return 0;
  41. }
Success #stdin #stdout 2.08s 5308KB
comments (?)
stdin
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43
stdout
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1: 433494437
2: 433494437
3: 433494437
https://ideone.com/qoNX1n
language:
C (gcc 8.3)
created:
15 days ago
visibility:
public

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