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import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class Main {
public static void main(String[] args) {
String numbers="123";
System.out.println("## 1234");
String tempNumbers[] = numbers.split("");
List<String> arr = Arrays.asList(tempNumbers);
ArrayList<String> returnArr = new ArrayList<>();
returnArr = result(arr,returnArr,"");
System.out.println(returnArr);
System.out.println("Hello World!");
}
public static ArrayList<String> result(List<String> arr, ArrayList<String> returnArr, String temp){
String loopTemp=temp;
for(int i=0;i<arr.size();i++) {
loopTemp += arr.get(i);
returnArr.add(loopTemp);
if(arr.size()!=1){
ArrayList<String> tempArr = new ArrayList<>(arr);
tempArr.remove(i);
result(tempArr,returnArr,loopTemp);
}
loopTemp = temp;
}
return returnArr;
}
}
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