why WA1????? please, help.



#include<iostream>
#include <stdio.h>
#include<string>

using namespace std;

 string s;

int main()
{
   #ifndef ONLINE_JUDGE
        freopen("input.txt","r",stdin);
        freopen("output.txt","w",stdout);
     #endif


    cin>>s;
    int  i=0;

    while (s[i]!=0)
     {
      if(s[i]==s[i+1])
      {
       s.erase(i,2);
       i--;
      }
       else
       i++;
    }
    cout<<s;
  return 0;
}

If I understand your code right, you think there is only one number in line. It is not right