运行下方代码段，输出的是( )。
try:
if s > 0:
s = s + 1
print(s)
except SyntaxError as e:
print("语法错误")
except NameError as e:
print("变量未赋值")
else:
print("出现未知错误")
s
语法错误
变量未赋值
出现未知错误