packagemethod; / 四则运算计算器 / importjava.util.Scanner; publicclassDemo07 { publicstaticvoidmain(String[]args) { Scannerscanner=newScanner(System.in); inta=0; intnum1=0,num2=0; System.out.println("请选择运行方法"); System.out.println("1.加法\t2.减法\t3.乘法\t4.除法"); if(scanner.hasNextInt()) { a=scanner.nextInt(); ...