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#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define u64 unsigned long long int

int main() {

        u64 t,a,b,c,k,m;
        int found;

        a = 0;
        b = 1;
        k = 1;

        scanf("%Lu", &t);
        m = 10; while (m<t) m*=10;

        found = 0;
        while (!found) {
                k++;

                a += b;
                a %= m;
                c = b;
                b = a;
                a = c;

                if (a==0 && b==1) break;

                if (b == t) found = 1;
        }

        if (found) printf("%Lu\n", k);
        else printf("NIE\n");

        return 0;

}