Java两层for循环

for(int i = 1;i <= 9; i++)
{for(int j = 1;j <=i; j++)
{system.out.print("");//输出上三角}
system.out.println();
}
for(int i = 1;i <= 9; i++)
{for(int j = i;j <=9; j++)
{system.out.print("");//输出下三角}
system.out.println();
}