stu=0 #ѧԱ³É¼¨
i=0 #ѧԱÈËÊý
while True:
num= input£¨'ѧԱµÄ³É¼¨£¨ÊäÈëq»òQÍ˳ö£©:'£©
if num == 'q'or num =='Q':
print£¨'Í˳ö'£©
break
a=int£¨num£©
if a>100 or a<=0:
print£¨'ÊäÈëÎÞЧ,ÖØÐÂÊäÈë'£©
continue
stu += a
i += 1
s= stu/i
print£¨'¹²',i,'ÃûѧԱ','ƽ¾ù³É¼¨',s£©
else:
print£¨'ûÓÐÊäÈëÓÐЧ³É¼¨'£©

¿Îºó×÷Òµ:a = 0
b =0
while True :
mark = input£¨"ÇëÊäÈëѧԱ³É¼¨£¨ÊäÈëq»òQ²àÍ˳ö£©"£©
if mark =="q" or mark =="Q" :
print£¨"¼ÈëÍê³É£¬Í˳ö"£©
break
if int£¨mark£© <0 :
print£¨"¼Èë³É¼¨ÎÞЧ"£©
continue
a +=1
b +=int£¨mark£©
print£¨"Ò»¹²Â¼ÈëÁË",a,"¸öѧԱ"£©
print£¨"ѧԱµÄƽ¾ù³É¼¨Îª£º",b/a£©

c = 0
b = 0

for i in range£¨3£©:
a = int£¨input£¨"ÇëÊäÈëѧԱ³É¼¨ £¨ÊäÈëq»òQÔòÍ˳ö£©"£©£©
if a == "q" or a == "Q":
break
elif a < 0 :
print£¨"¼ÈëµÄ³É¼¨ÎÞЧ"£©
continue
b = b + c
c += a
else:
print£¨"¼ÈëÍê³É£¬Í˳ö"£©
bc = c // 3
print£¨bc£©

¿Îºó×÷Òµ:

su = 0
i = 0
while True:
a = input£¨"ÇëÊäÈëѧԱ³É¼¨:"£©
if a == "q" or a == "Q":
print£¨"Ò»¹²Â¼È룺",i,"¸öѧԱ"£©
print£¨"ѧԱƽ¾ù³É¼¨Îª:",su/i£©
break
elif int£¨a£© < 0:
print£¨"¼Èë³É¼¨ÎÞЧ"£©
else:
su += int£¨a£©
i += 1

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i=0
s=0
while True:
a=£¨input£¨"ÇëÊäÈëѧԱ³É¼¨£¨q»òQÍ˳ö£©£º"£©£©
if a=="q" or a=="Q" :
print£¨"¼ÈëÍê³É£¬Í˳ö¡£"£©
break
score=float£¨a£©
s=s+score
if score<0:
print£¨"¼ÈëµÄ³É¼¨ÎÞЧ"£©
continue
i +=1
avr=s/i
print£¨"Ò»¹²Â¼ÈëÁË",i,"¸öѧԱ"£©
print£¨"ѧԱµÄƽ¾ù³É¼¨Îª",avr£©

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