Find Active, Inactive, Total user in Groups across salesforce org

GroupUsersCalculation.java

List < Group > lstGroupReg = [Select Id from Group where Type = 'Regular'];
List < User > lstInActiveUser = [Select Id from user where IsActive = false];
Set < id > SetInactiveUser = new Set < id > ();
for (User objUser: lstInActiveUser) {
    SetInactiveUser.add(objUser.id);
}
List < GroupMember > lstGM = [Select Id, UserOrGroupId, GroupId from GroupMember where GroupId IN: lstGroupReg];
//system.debug(lstGM.size());

map < String, Integer > mapGroupToInActive = new Map < String, Integer > ();
map < String, Integer > mapGroupTotal = new Map < String, Integer > ();

for (GroupMember objGM: lstGM) {
    if (SetInactiveUser.contains(objGM.UserOrGroupId)) {
        if (mapGroupToInActive.containsKey(objGM.GroupId))
            mapGroupToInActive.put(objGM.GroupId, mapGroupToInActive.get(objGM.GroupId) + 1);
        else
            mapGroupToInActive.put(objGM.GroupId, 1);
    } else {
        mapGroupToInActive.put(objGM.GroupId, 0);
    }


    if (mapGroupTotal.containsKey(objGM.GroupId))
        mapGroupTotal.put(objGM.GroupId, mapGroupTotal.get(objGM.GroupId) + 1);
    else
        mapGroupTotal.put(objGM.GroupId, 1);
}


String csvHeader = 'GroupId total inactive \n';
List < String > csvRows = new List < String > ();
for (String str: mapGroupTotal.keyset()) {
    csvRows.add(str + ' ' + mapGroupTotal.get(str) + ' ' + mapGroupToInActive.get(str));
}

String CsvFiletotal = csvHeader + String.join(csvRows, '\n');
system.debug(':::::::');
system.debug(CsvFiletotal);