Important things in Java

int [] A = new int [n];

for (int x : A) System.out.println (x);

int[] array = new int[4];
Arrays.fill(array, 0);

System.out.println(Arrays.deepToString(array));

Math.max (a, b)

Math.abs (a)

StringBuilder:

StringBuilder res = new StringBuilder ();

res.append (char ('A'));

res.append (String);

String ans = res.toString();

int[] array = new int[4];
Arrays.fill(array, 0);

Arrays.Sort (object[], startIndex, endIndex);

Set st = new HashSet  ();
st.add (5);
st.size();

List  list = new ArrayList  ();
Concerting Set to List type
List  list = new ArrayList  (st);
Collection.sort (list);

String s = new String();
s.toCharArray();

Input Output Code in Java (Code is taken from Egor's library).



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If you want to use something other, this is Parser class for input (Written by Rudradevbasak's team proof). For output, you can use PrintWriter class which is fast enough.