# Write a function called "position" that returns a tuple of the first uppercase letter and its index location. If not found, returns -1. 剛剛在寫這個很簡單的 def position(string): for num, s in enumerate(string): # enumerate (iterable, start=0) if s == s.upper(): print((s, num)) return (s, num) print(-1) return -1 enumerate很好寫沒有問題 但我剛剛想說用index寫寫看 def position(string): for index in range(0, len(string)): if string[index] == string[index].upper(): print((string[index], index)) print(-1) return -1 position("abcd") # returns -1 position("AbcD") # returns ('A', 0) position("abCD") # returns ('C', 2) 理論上上下兩者return都會這樣 但後者卻長這樣 ('A', 0) ('D', 3) -1 ('C', 2) ('D', 3) -1 def position(string): for index in range(0, len(string)): if string[index] == string[index].upper(): print((string[index], index)) return (string[index], index) print(-1) return -1 我補上return這行才正確 -1 ('A', 0) ('C', 2) 有沒有人可以跟土法煉鋼學習的我解釋一下這個return扮演甚麼角色 我只是很直覺得加上去，就寫對了== 不懂why -- 色情兔兔真讚 https://imgur.com/8YI1yju.jpg 89011978/Choney https://imgur.com/1v81UqN.jpg 3646291/Armadillo https://imgur.com/miLxbrs.jpg 90838107/HEIJUN・玉田平準 https://imgur.com/jKug6M4.jpg 88459182/Yuyu https://imgur.com/NEsfFYI.jpg 80081010/Moisture 南丁我婆 -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 103.131.12.26 (澳大利亞) ※ 文章網址: https://www.ptt.cc/bbs/Marginalman/M.1722397818.A.1BA.html