anzahl "Programmierung" 'm' == 2
anzahl "Programmierung" '+' == 0

haeufigkeit "Otto" == [('o',1),('t',2)]
haeufigkeit "Studass@g0" == [('a',1),('d',1),('g',1),('s',2),('t',1),('u',1)]

gmedian [3,5,6,8,9,10] == 6
gmedian [3,6,5,9,8] == 6
gmedian [] == 2008
gmedian [3,5,9,3] == 2008

ersetze "Hohoho" 4 "o" "a" == "Hohoho"
ersetze "Hohoho" (-2) "ho" "ha" == "Hohoho"
ersetze "Hohoho" 2 "o" "ey" == "Hoheyho"