1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
#include <iostream>
#include <string>

using namespace std;

long long pot=1,fib0=0,fib1=1,fib;
long long dl,x=0;
string s;
bool odp=0;

int main()
{
    cin >>s;
    dl=s.size();
    for (int i=0;i<dl;i++)
    {
        x=x*10+s[i]-48;
        pot=pot*10;
    }
    for(long long i=2;i<10000000;i++)
    {
        fib=(fib0+fib1)%pot;
        fib0=fib1;
        fib1=fib;
        if (fib ==x) {cout <<i<<endl; odp=1; break;}
    }
    
    if (odp==0) cout <<"NIE"<<endl;
    
}