import java.util.*;class G{public static void main(String[]args){char[] out=new char[9999];Scanner sc=new Scanner(System.in);String s="";s=sc.nextLine();out=s.toCharArray();int b=0;int c=0;for(int i=0;i<out.length;i++){int a=out[i];if(i>2){b=out[i-1];c=out[i-2];}if(a>=65&a<=90|a==32&b==32&c==32|a==46|a==40|a==41|a==45&b==32|a>=48&a<=57|a==44)System.out.print(out[i]);}}}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).