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import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigInteger;

public class fib {

	public static void main(String args[]) throws IOException {		
		BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
		System.out.println(getFib(bufferedReader.readLine()));
		bufferedReader.close();		
	}

	private static String getFib(String digits) {
		long[] buffer = { 0, 1 };
		long fib;
		long fibSmaller;		
		int len = digits.length();
		int timesCut = 0;
		long allowedTimesCut = (long)Math.min(1000000, Math.pow(10, len));
		long digitsLong = new Long(digits);

		BigInteger k = new BigInteger("2");
		BigInteger limit = new BigInteger("10").pow(100);

		boolean sizeOk = len == 1;

		while (timesCut < allowedTimesCut && k.compareTo(limit) <= 0 ) {
			fib = (buffer[0] + buffer[1]);
			if (!sizeOk && fib > Math.pow(10, len - 1)) {
				sizeOk = true;
			}
			fibSmaller = fib % (long) Math.pow(10, len);
			if (fib != fibSmaller) {
				fib = fibSmaller;
				timesCut++;
			}			
			if (sizeOk && fib == digitsLong) {				
				return k.toString(10);
			}			
			k = k.add(BigInteger.ONE);
			buffer[0] = buffer[1];
			buffer[1] = fib;
		}
		return "NIE";
	}
}