#include<string.h>
#include<cassert.h>
using namespace std;
int main() {
string s1="This ";
string s2=("That ");
string s3=("The other ");
s1 = s1 + s2;
assert(s1 == "This That ");
s1 += s3;
assert(s1 == "This That The other ");
s1 += s3 + s3[4] + "ooh lala";
assert(s1 == "This That The other The other "
"ooh lala");
getch();
}