#include <iostream> #include <algorithm> #include <cmath> #include <cstring> using namespace std; string Add(string s1, string s2) { int l1 = s1.size(), l2 = s2.size(); if (l1 < l2)swap(s1, s2); reverse(s1.begin(), s1.end()); reverse(s2.begin(), s2.end()); int car = 0; str...