t,s=map(float, raw_input().split())
if s%5==0 :
if t> s+0.5 :
t-=s+0.5
print('%.2f' % t)
else :
print ('low balance')
else :
print ('%.2f' % t)
remove the line:
print(‘low balance’)
it should be:
print(’%.2f’ %t)
which just returns the original value of t