#include <bits/stdc++.h>
using namespace std;
string s1,s2;
int main()
{
	while(cin>>s1>>s2)
	{
		int flag=0;
		int i,j;
		for(i=0,j=0;i<s1.size();i++)
		{
			while(s1[i]!=s2[j]&&j<s2.size())j++;
			//cout<<i<<" "<<j<<endl;
			if(j>=s2.size()) {
			flag=1;
			break;
			}
			j++;
		}
		if(i==s1.size()&&!flag) puts("Yes");
		else puts("No");
	}
	return 0;
}