@C++
#include<bits/stdc++.h>
using namespace std;
int main(){
char a[5];
for(int i=0;i<5;i++){
cin>>a[i];
}
cout<<strlen(a)<<endl;
a[2]='\0';
for(int i=0;i<5;i++){
cout<<a[i]<<endl;
}
cout<<a[4]<<endl;
cout<<strlen(a)<<endl;
cout<<sizeof(a)<<endl;
//cout<<a.length()<<endl;报错
cout<<"xxxxxxxxxxxx"<<endl;
string b;
cin>>b;
cout<<b<<endl;
cout<<sizeof(b)<<endl;
//cout<<strlen(b)<<endl;报错
cout<<b.length()<<endl;
}