اعداد اولوناچی

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#include <iomanip> 
#include <iostream> 
#include <vector> 
using namespace std; 
 
const int MAX = 1000*1000; 
 
vector<int> fibo; 
 
int main() { 
  fibo.push_back(2); 
  fibo.push_back(3); 
  while (true) { 
    int n = fibo.size(); 
    int k = fibo[n-1] + fibo[n-2]; 
    if (k > MAX) break; 
    fibo.push_back(k); 
  }   
 
  int all = 0, good = 0; 
  for (int i=MAX/10; i<MAX; i++) { 
    all++; 
    for (int j=0; j<fibo.size() && fibo[j] <= i; j++) 
      if (i % fibo[j] == 0) 
        goto hell; 
    good++; 
  hell: ; 
  }   
 
  double d = double(good) / all * 100; 
  cerr << fixed << setprecision(10) << d << endl; 
 
  return 0; 
}