import java.io.*;
import java.util.*;
public class GFG {
public static void maxLength(int lis[], int n)
{
lengthy or = 0;
for (int i = 0; i < n; i++) = lis[i];
int[] rely = new int[32];
for (int i = 0; i < n; i++) {
for (int j = 0; j < 32; j++) {
if ((lis[i] & (1L << j)) != 0)
rely[j]++;
}
}
lengthy ans = 0, l = 0, tempOr = 0;
for (int r = 0; r < n; r++) {
tempOr |= lis[r];
boolean flag = true;
for (int i = 0; i < 32; i++) {
if ((lis[r] & (1L << i)) != 0) {
rely[i]--;
if (rely[i] == 0)
flag = false;
}
}
if (!flag) {
for (; l <= r;) {
boolean flag1 = true;
for (int i = 0; i < 32; i++) {
if ((lis[(int)l] & (1L << i))
!= 0) {
rely[i]++;
}
if (rely[i] == 0)
flag1 = false;
}
l++;
if (flag1)
break;
}
}
if (tempOr == or) {
ans = Math.max(ans, r - l + 1);
}
}
if (ans != 0)
System.out.println(ans);
else
System.out.println(-1);
}
public static void important(String[] args)
{
String S = "2347";
int N = S.size();
int[] A = new int[N];
for (int i = 0; i < N; i++) {
A[i] = S.charAt(i) - '0';
}
maxLength(A, N);
}
}
