python函數寫法_python函數入門

x=print('a')#傳回a

print(a)  #傳回None

下面介紹三種分數的程式員

a=[1,2,3,4]  #想讓輸出結果顯示次數和數字一樣(按總分五分來比較)

顯示結果為：

1

22

333

4444

第一種方法：  (三分)                               第二種方法： (四分)

for x in a：                                               for  x in a:

if x==1：                                                  if x==1:

print(x)                                                 print('1')

elif x==2：                                                if x==2:

print(str(x)*2)                                     print('22')

else：#else後面不能跟條件                            if x==3:

if x==3：                                                   print('333')

print(str(x)*3)                               if x=4:

else：                                                         print('4444')

print(str(x)*4)

第三種方法：(五分)

for x in  a：

print(str(x)*x)

當需求變更為(a=[1,2,3,4,5,6,7,8])，第一種必須改改能實作基本功能， 顯然比較麻煩

第二種也需要增加，簡捷友善一點

第三種則不需要改變，最簡潔省事

下面我将用函數來寫一下：

第一種函數寫法：                                                                                        第二種函數寫法  ：

def jiang(shuzu)：                                                                                                             def jiang(a=[1，2，3，4])：

for  x  in  shuzu：#shuzu是變量名 、局部變量、 型式參數                                                                for x in a：

print(str(x)*x)                                                                                                                   print(str(x)*x)

jiang(a)                                                                                                                                jiang()