In [14]:
n = int(raw_input())
result = {}
for i in xrange(n):
name,math,phy,chem = raw_input().split()
result[name] = (float(math)+float(phy)+float(chem))/3.0;
name = raw_input()
if name in result:
print '%.2f' %result[name]
In [ ]: