用C++连接字符串和数字

#include <iostream>
#include <sstream>
using namespace std;

int main() {
   string str = "Hello";
   int num = 123;
   
   stringstream ss;
   ss << str << num;
   
   string result = ss.str();
   
   cout << result << endl; // 输出：Hello123
   
   return 0;
}

#include <iostream>
using namespace std;

int main() {
   string str = "Hello";
   int num = 123;
   
   string result = str + to_string(num);
   
   cout << result << endl; // 输出：Hello123
   
   return 0;
}