1.10

#include <iostream>
#include <string>using namespace std;int main(){string string1;string string2;cout << "input string1:" << endl;cin >> string1;cout << "input string2:" << endl;cin >> string2;cout << "string1:" << endl << string1 << endl;cout << "string2:" << endl << string2 << endl;string1.append(string2);cout << "string1.append():" << endl << string1 << endl;return 0;}