// 12判断string类型字符串是否为空 /*#include <iostream> #include <string> using namespace std; int main() { string s1 = ""; if(s1.empty()){ cout<<"s1为空"<<endl; }else{ cout<<"s1不为空:"<<s1<<endl; } return 0; */
// 12判断string类型字符串是否为空 /*#include <iostream> #include <string> using namespace std; int main() { string s1 = ""; if(s1.empty()){ cout<<"s1为空"<<endl; }else{ cout<<"s1不为空:"<<s1<<endl; } return 0; */