why my code stop in secound while loop?
<p><strong>#hello , i wounder why my code keep stoping at the secound while loop and doesn't do anything</strong></p>

<pre><code>print"*******************************"
a = 0
deg_list =[]
deg_list_a=[]
deg_list_b=[]
deg_list_c=[]
degree=input("Enter the students Degree:")
while a&lt;=degree:
    deg_list.append(degree);
    degree=input("Enter the students Degree:")
print "Degree List :",deg_list
print len(deg_list)
while len(deg_list)&gt;=0:
    if deg_list[a]&gt;=16:
        deg_list_a.append(deg_list[a])
        x=+1
    elif 15&gt;deg_list[a]&gt;=10:
        deg_list_b.append(deg_list[a])
        x=+1
    else :
        deg_list_b.append(deg_list[a])
        x=+1
print deg_list_a
print deg_list_b
print deg_list_c
</code></pre>
