go实现小项目

package main
import "fmt"
func main() {
	key:="";
	loop:=true;
	detail:="收支\t账户余额\t收支金额\t说明";
	money:=0.0;
	banacle:=1000.00;
	notes:="";
	details:="";

	for {
		fmt.Println("\n-------------------家庭收支记账软件-----------------------");
		fmt.Println("                   1.收支明细");
		fmt.Println("                   2.登记收入");
		fmt.Println("                   3.登记支出");
		fmt.Println("                   4.退出软件");
		fmt.Println("请选择(1-4):");
		fmt.Scanln(&key);
		switch key {
		case "1":
			fmt.Println("本次收入:");
			fmt.Scanln(&money);
			banacle=banacle+money;//收入
			fmt.Println("收入来源是:");
			fmt.Scanln(&notes);
			fmt.Println("-------------------收支明细记录-----------------------");
			fmt.Println(detail);
			//detailstr:="收入\t%v\t%v\t%v";
			details+=fmt.Sprintf("\n收入%12v\t%10v\t%12v",banacle,money,notes);
			fmt.Println(details);

		case "2":
				fmt.Println("this is 2");
		case "3":
			fmt.Println("这是登记支出");
		case "4":
			loop=false;
		}
		if !loop {
			break;
		}
		
	}
}