我有以下数据集，我想根据重复次数将此数据更改为目标输出数据集

Question

I have below dataset and i want to make repititions of my rows that number of times and assign index to them.

Thanks in advance. Every suggestion is appreciated :)

INPUT:

Col1    col2    col3    repetition
101 test1   10      2
102 test2   20      1
103 test3   30      2
104 test4   40      1

OUTPUT:

col1            col2           col3       index
101     test1       10      1
101     test1       10      2
102     test2       20      1
103     test3       30      1
103     test3       30      2
104     test4       40      1

Answer 1

Here is some java code that describes the algorithm to accomplish this:

 List<InputType> inputList = getInput(); List<OutputType> outputList = new ArrayList<>(); foreach(InputType input in inputList){ for(int index = 1; index <= input.repetition){ OutputType output = new OutputType(input.col1, input.col2, input.col3, index); outputList.add(output) } } System.out.println(outputList);