

import java.io.*;
import java.util.*;


public class Main {

    public static void main(String[] args) {
	// write your code here
        BufferedReader bf;
        try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        }

        try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        }
    }

}
class pA {
    int res;
    char[] bucket;
    pA() {} ;
    pA(String msg)
    {
        res=0;
        bucket=new char[msg.length()];
        for(int i=0;i<msg.length();i++)
        {
            bucket[i]=msg.charAt(i);
        }
        solver();
    }
    int solver()
    {
        boolean duplicateFlag=false;
        for(int i=0;i<bucket.length;i++)
        {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        }
        return 0;
    }
} import java.io.*; io.* java import java.util.*; util.* java public class Main {

    public static void main(String[] args) {
	// write your code here
        BufferedReader bf;
        try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        }

        try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        }
    }

} Main public static void main(String[] args) {
	// write your code here
        BufferedReader bf;
        try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        }

        try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        }
    } main {
	// write your code here
        BufferedReader bf;
        try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        }

        try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        }
    } BufferedReader bf; bf try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        } catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        } FileNotFoundException e {
            bf = new BufferedReader(new InputStreamReader(System.in));
        } bf = new BufferedReader(new InputStreamReader(System.in)) bf new BufferedReader(new InputStreamReader(System.in)) {
                bf = new BufferedReader(new FileReader("in1.log"));
        } bf = new BufferedReader(new FileReader("in1.log")) bf new BufferedReader(new FileReader("in1.log")) try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        } catch (IOException e) {
            System.exit(0);
        } IOException e {
            System.exit(0);
        } System.exit(0) System.exit System 0 {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } pA p = new pA( bf.readLine()); p new pA( bf.readLine()) if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            } p.res==2 p.res p p.res 2 System.out.println("Yes") System.out.println System.out System System.out "Yes" {
                System.out.println("No");
            } System.out.println("No") System.out.println System.out System System.out "No" String[] args args class pA {
    int res;
    char[] bucket;
    pA() {} ;
    pA(String msg)
    {
        res=0;
        bucket=new char[msg.length()];
        for(int i=0;i<msg.length();i++)
        {
            bucket[i]=msg.charAt(i);
        }
        solver();
    }
    int solver()
    {
        boolean duplicateFlag=false;
        for(int i=0;i<bucket.length;i++)
        {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        }
        return 0;
    }
} pA int res; res char[] bucket; bucket pA() {} pA {} pA(String msg)
    {
        res=0;
        bucket=new char[msg.length()];
        for(int i=0;i<msg.length();i++)
        {
            bucket[i]=msg.charAt(i);
        }
        solver();
    } pA {
        res=0;
        bucket=new char[msg.length()];
        for(int i=0;i<msg.length();i++)
        {
            bucket[i]=msg.charAt(i);
        }
        solver();
    } res=0 res 0 bucket=new char[msg.length()] bucket new char[msg.length()] msg.length() msg.length msg for(int i=0;i<msg.length();i++)
        {
            bucket[i]=msg.charAt(i);
        } int i=0; int i=0; i 0 i<msg.length() i msg.length() msg.length msg i++ i++ i {
            bucket[i]=msg.charAt(i);
        } {
            bucket[i]=msg.charAt(i);
        } bucket[i]=msg.charAt(i) bucket[i] bucket i msg.charAt(i) msg.charAt msg i solver() solver String msg msg int solver()
    {
        boolean duplicateFlag=false;
        for(int i=0;i<bucket.length;i++)
        {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        }
        return 0;
    } solver {
        boolean duplicateFlag=false;
        for(int i=0;i<bucket.length;i++)
        {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        }
        return 0;
    } boolean duplicateFlag=false; duplicateFlag false for(int i=0;i<bucket.length;i++)
        {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        } int i=0; int i=0; i 0 i<bucket.length i bucket.length bucket bucket.length i++ i++ i {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        } {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        } duplicateFlag=false duplicateFlag false for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            } int j=0; int j=0; j 0 j<i j i j++ j++ j {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            } {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            } if(bucket[i]==bucket[j])
                    duplicateFlag=true; bucket[i]==bucket[j] bucket[i] bucket i bucket[j] bucket j duplicateFlag=true duplicateFlag true if(duplicateFlag==false)
                res+=1; duplicateFlag==false duplicateFlag false res+=1 res 1 return 0; 0 public class Main {

    public static void main(String[] args) {
	// write your code here
        BufferedReader bf;
        try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        }

        try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        }
    }

} public class Main {

    public static void main(String[] args) {
	// write your code here
        BufferedReader bf;
        try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        }

        try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        }
    }

} Main


import java.io.*;
import java.util.*;


public class Main {

    public static void main(String[] args) {
	// write your code here
        BufferedReader bf;
        try {
                bf = new BufferedReader(new FileReader("in1.log"));
        }
        catch (FileNotFoundException e)
        {
            bf = new BufferedReader(new InputStreamReader(System.in));
        }

        try {
            pA p = new pA( bf.readLine());
            if(p.res==2)
                System.out.println("Yes");
            else {
                System.out.println("No");
            }
        } catch (IOException e) {
            System.exit(0);
        }
    }

}
class pA {
    int res;
    char[] bucket;
    pA() {} ;
    pA(String msg)
    {
        res=0;
        bucket=new char[msg.length()];
        for(int i=0;i<msg.length();i++)
        {
            bucket[i]=msg.charAt(i);
        }
        solver();
    }
    int solver()
    {
        boolean duplicateFlag=false;
        for(int i=0;i<bucket.length;i++)
        {
            duplicateFlag=false;
            for(int j=0;j<i;j++)
            {
                if(bucket[i]==bucket[j])
                    duplicateFlag=true;
            }
            if(duplicateFlag==false)
                res+=1;
        }
        return 0;
    }
}
