import java.util.Scanner; public class Main { public static String getSum(String s1, String s2) { String sum = ""; char[] c1, c2; //add_bit来自低位保存进位值 int n1, n2, add_bit = 0; if (s1.length() < s2.length()) { c1 = s1.toCharArray(); c2 = s2.toCharArray(); } else { c1 = s2.toCharArray(); c2 = s1.toCh...