#include<bits/stdc++.h>
using namespace std;


#define ff first
#define ss second
#define pb push_back
#define ll long long int
#define all(v) (v).begin(),(v).end()
#define set_bits __builtin_popcountll  


void solve()
{
   string s,s1;
   cin>>s>>s1;
   if(s[0]!=s1[0])
   {
    cout<<"No"<<endl;
   }
   else
   {
    int j=0;
    int c=0;

    for (int i = 0; i < s.size(); ++i)
    {
        if(s[i]==s1[j])
        {
            j++;
            c=0;
        }
        else
        {
            if(s1[j]==s[i-1]&&c==0)
            {
                cout<<"No"<<endl;
                return;
            }
            else
            {
                c=1;
                i--;
                j++;
            }
        }
    }
    cout<<"Yes"<<endl;
   }
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);


    /*int t;
    cin>>t;
    while(t--)*/
    {
        solve();
    }
    return 0;

}