public static void main(String[] ar) {
String str = " ,,,124,5,5, ";
System.out.println(str.contains("123"));
List<Integer> list = new ArrayList<>();
list.add(1);
list.add(2);
list.add(3);
list.add(4);
list.add(5);
list.add(3,31);
System.out.println(list);
}
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