I will list down the specifics. The first column is a group number which will always be a numeric value ranging from 1 to 6. The second column can be any string but there can be only two unique values for each group according to the first column. Only one value can repeat in more than one group and that value is fixed. For example if we assume that BBBB is the value which repeats in each group(it can repeat doesnt mean it will repeat, it may happen that it might not be present in any group), then there will only be one other string in group one, but that string can repeat any number of time according to the group strength.