#include "iostream"
#include "string"
#include "cstring"
using namespace std;
#define size 10
int main()
{
    char s1[size]="1", s2[size]={0};
    for(int i=0; i<10; i++) cout<<s1[i]<<"";
    cout<<endl;
    for(int i=0; i<10; i++) cout<<s2[i]<<"";
    cout<<endl;
    cout<<"s1.length="<<strlen(s1)<<endl;
    cout<<"s2.length="<<strlen(s2)<<endl;
    for(int i=0; i<2; i++) s1[i] = '0';
    for(int i=0; i<10; i++) cout<<s1[i]<<"";
    cout<<endl;
    for(int i=0; i<2; i++) s2[i] = '1';
    for(int i=0; i<10; i++) cout<<s2[i]<<"";
    cout<<endl;
    cout<<"s1.length="<<strlen(s1)<<endl;
    cout<<"s2.length="<<strlen(s2)<<endl;
    for(int i=0; i<2; i++) s1[i] = 'a';
    for(int i=0; i<10; i++) cout<<s1[i]<<"";
    cout<<endl;
}