根据用户输出的数字输出以下成语
switch(a) { case 1: b = "一帆风顺"; break; case 2: b = "二龙戏珠"; break; case 3: b = "三阳开泰"; break; case 4: b = "四平八稳"; break; case 5: b = "五福临门"; break; case 6: b = "六六大顺"; break; case 7: b = "七星报喜"; break; case 8: b = "八面威风"; break; case 9: b = "九九归一"; break; case 10: b = "十全十美"; break; default: b = "输入有误"; }