Each of the four Java functions below returns a string of length N whose characters are all

**1. **

public static String method1(int N) { String s = ""; for (int i = 0; i < N; i++) s = s + "x"; return s; }

public static String method2(int N) { if (N == 0) return ""; if (N == 1) return "x"; return method2(N/2) + method2(N - N/2); }

public static String method3(int N) { char[] temp = new char[N]; for (int i = 0; i < N; i++) temp[i] = 'x'; return new String(temp); }