我想强制用户选择1,然后才能继续选择2,任何帮助都会受到赞赏。 (注意我到目前为止只执行过if,while,for,do .... while,java中的方法和数组)
Scanner sc = new Scanner(System.in);
int[] ages = new int[3];
int choice;
do {
System.out.println("Average Age program");
System.out.println("Enter 1 to enter ages");
System.out.println("Enter 2 to calculate the average Age");
System.out.println("Enter 0 to Exit");
choice = sc.nextInt();
switch(choice) {
case 1:
acceptAges(ages);
break;
case 2:
averageAge(ages);
break;
default:
System.out.print("invalid option");
}
} while(choice != 0);
}
答案 0 :(得分:0)
在2
被选中至少一次之前,您无法显示选择1
。
Scanner sc = new Scanner(System.in);
int[] ages = new int[3];
int choice;
boolean is2Enabled=false,
do{
System.out.println("Average Age program");
System.out.println("Enter 1 to enter ages");
if(is2Enabled)
System.out.println("Enter 2 to calculate the average Age");
System.out.println("Enter 0 to Exit");
choice=sc.nextInt();
switch(choice)
{
case 1:
acceptAges(ages);
is2Enabled=true;
break;
case 2:
if(is2Enabled)
averageAge(ages);
else
System.out.print("invalid option");
break;
default:
System.out.print("invalid option");
}
}while(choice != 0);
}