import java.util.Scanner; public class StringToNum { public static void main(String[] args) { Scanner scan = new Scanner(System.in); System.out.println("请输入第一个数字:"); String s1 = scan.nextLine(); System.out.println("请输入第二个数字:"); String s2 = scan.nextLine(); int i = Integer.parseInt(s1) +Integer.parseInt(s2) ; System.out.println(i); } }