<p>我在这里看到的一个问题是,您试图对字符串而不是数字执行不等式。尝试将输入值转换为整数。你知道吗</p>
<p>如果将fgrades中的值存储为整数,例如[90、70、60、88、96],那么这应该可以:</p>
<pre><code>fgrades=[90, 70, 60, 88, 96]
a=0
b=0
c=0
d=0
f=0
grades=raw_input("enter your final grade: ")
# Clean up grades, and convert to an integer
grades = int(grades.strip().replace(" ","")
fgrades.append(grades)
for i in range(len(fgrades)):
if fgrades[i]>=90:
a+=1
elif fgrades[i]>=80:
b+=1
elif fgrades[i]>=70:
c+=1
elif fgrades[i]>=60:
d+=1
else:
f+=1
print a,"\n",b,"\n",c,"\n",d,"\n",f
</code></pre>
<p>否则,如果出于某种原因要求将成绩存储为字符串,例如[“90”、“70”、“63”、“81”、“49”],则以下内容适用于您:</p>
<pre><code>fgrades= ["90","70","63","81","49"]
a=0
b=0
c=0
d=0
f=0
grades=raw_input("enter your final grade: ")
# Clean up grades
grades = grades.strip().replace(" ","")
fgrades.append(grades)
for i in range(len(fgrades)):
if int(fgrades[i])>=90:
a+=1
elif int(fgrades[i])>=80:
b+=1
elif int(fgrades[i])>=70:
c+=1
elif int(fgrades[i])>=60:
d+=1
else:
f+=1
print a,"\n",b,"\n",c,"\n",d,"\n",f
</code></pre>