亂序的問題

習題133.Five distinct toys are distributed to five children ( one toy to each child ). In how many ways can these five distinct toys be collected and redistributed to the five children so that each child gets one different toy from the first distribution？

參考上課老師講的

15位學生上兩門課，每位學生兩門課位置皆不同有幾種可能？

答案是15!*D15，而答案本上習題133的答案卻是D5，可是我覺得2題的題意是一樣的

麻煩請高手幫忙解答一下，感謝