I have a dataframe with two columns, region and number of user. Region is sometimes combination of countries and continent (see below the dummy sample). Ex: user number for Oceania (New Zeland included) and New Zeland.
I am looking for a way to subtract country number from continent row, in other word having two rows without duplication, Oceania(without New Zeland) and New Zeland. Same for Europe and Germany, etc

Here the sample data

```
df = data.frame(
  regions_user = c(2200, 1250, 900, 21200, 14200, 150000, 35000, 41900),
  regions_names = c(
    "Oceania",
    "New Zeland",
    "Africa",
    "North America",
    "Asia",
    "Europe",
    "Germany",
    "Latin America"
  ))

#sample data output

  regions_user regions_names
1         2200       Oceania
2         1250    New Zeland
3          900        Africa
4        21200 North America
5        14200          Asia
6       150000        Europe
7        35000       Germany
8        41900 Latin America

#desired output

regions_user regions_names
1          950       Oceania
2         1250    New Zeland
3          900        Africa
4        21200 North America
5        14200          Asia
6       115000        Europe
7        35000       Germany
8        41900 Latin America

```