python solution

使用贪心算法。

import sys

for i in sys.stdin.readlines():
    str1, str2 = i.strip().split()
    for i in str1:
        if str2 and i == str2[0]:
            str2 = str2[1:]
    print("Yes" if not str2 else "No")

#include <cstdio>
#include <limits.h>
#include <vector>
#include <functional>
#include <string>
#include <iostream>

using namespace std;

int main()
{
 //freopen("in.txt", "r", stdin);
 string s, t;
 while (cin >> s >> t)
 {
  if (s.size() < t.size())
  {
   cout << "No" << endl;
   continue;
  }
  int i = 0, j = 0;
  while (i < s.size() && j < t.size())
  {
   if (s[i] == t[j]) ++j;
   ++i;
  }
  cout << (j == t.size() ? "Yes" : "No") << endl;
 }

 return 0;
}

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		while(in.hasNext()){
			String s1=in.next();
			String s2=in.next();
			int len1=s1.length();
			int len2=s2.length();
			char[] cA1 = s1.toCharArray();
			char[] cA2 = s2.toCharArray();
			int i = 0, j = 0;
	        for(; i<len1 && j<len2;)
	        {
	            if(cA1[i] == cA2[j])
	            {
	                j++;
	            }
	            i++;
	        }
	         
	        if(j == len2)
	        {
	            System.out.println("Yes");
	        }
	        else
	        {
	            System.out.println("No");
	        }
		}
	}
}

#include<cstdio>
(802)#include<cstring> 
int main(){
    char str1[100010],str2[100010];
    while(scanf("%s %s",str1,str2)!=EOF){
        int k=0;
        int len1=strlen(str1);
        int len2=strlen(str2);
        for(int i=0;i<len1&&k<len2;i++){
            if(str1[i]==str2[k])
            {
                 k++;
            }
        }
        if(k==len2){
            printf("Yes\n");
        }else{
            printf("No\n");
        }
    }
    return 0;
}

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

int main() {
    char a[100001], b[100001];
    while(scanf("%s%s", a, b) != EOF) {
        int i, j, lena = strlen(a), lenb = strlen(b);
        for(i = j = 0; i < lena && j < lenb; ++i) {
            if(a[i] == b[j]) {
                ++j;
            }
            if(j == lenb){
                printf("Yes\n");
                break;
            }
        }
        if(j < lenb)
            printf("No\n");
    }
    return 0;
}

#include<iostream>
#include<string>
using namespace std;
int main()
{
	string str, res;
	while (cin >> str >> res)
	{
		int j = 0;
		bool sta = false;
		for (auto c : str)
		{
			if (c == res[j])
				j++;
			if (j == res.length())
			{
				sta = true;
				break;
			}
		}
		
		if (sta == true)
			cout << "Yes" << endl;
		else
			cout << "No" << endl;
	}
	return 0;
}

}

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner read = new Scanner(System.in);
		while(read.hasNext())
		{
			String str1 = read.next();
			String str2 = read.next();
			judgeStr(str1, str2);
		}
		read.close();
	}

	/**
	 * 
	 * @param source
	 * @param target
	 * @return
	 */
	public static int indexOf(char[] source, char[] target) {
		
		int targetCount = target.length;
		int sourceCount = source.length;
		
		if (targetCount == 0) {
			return 0;
		}

		char first = target[0];
		int max = sourceCount - targetCount;

		for (int i = 0; i <= max; i++) {
			if (source[i] != first) {
				while (++i <= max && source[i] != first)
					;
			}

			if (i <= max) {
				int j = i + 1;
				int end = j + targetCount - 1;
				for (int k = 1; j < end
						&& source[j] == target[k]; j++, k++)
					;

				if (j == end) {
					return i;
				}
			}
		}
		return -1;
	}
	
	public static void judgeStr(String str1, String str2)
	{
		int len1 = str1.length(), len2 = str2.length();
		
		int i = 0, j = 0;
		
		for(; i<len1 && j<len2;)
		{
			if(str1.charAt(i) == str2.charAt(j))
			{
				j ++;
			}
			i ++;
		}
		
		if(j == len2)
		{
			System.out.println("Yes");
		}
		else
		{
			System.out.println("No");
		}
	}
}