//		Задача номер 1 (ОДИН)
#include<fstream.h>
#include<string.h>
#include<stdlib.h>

void Insert(char* ch,int pos, char c)
{
  char tmp;
  int ii=pos;
  while (ch[ii]!='\0')ii++;
  for (int i=ii; i>pos; i--)
  {
    ch[i+1]=ch[i];
  }
  if (ch[1023]!='\0')exit(0);
  ch[pos]=c;
  return;
}


void main()
{
  ifstream in("input.txt",ios::nocreate);
  ofstream out("output.txt");
  char pre[127],post[127],base_line[128],result_line[1024];
  int precounter=0, postcounter=0,baselinecounter=0,resultlinecounter=0;
  unsigned char tmpchar[2];
  tmpchar[1]='\0';
  pre[0]=post[0]=result_line[0]=base_line[0]='\0';
  in>>base_line;
  strcpy(result_line, base_line);
  in.close();
  result_line[1023]='\0';
  while (base_line[baselinecounter]!='\0'){

/************* Nachalo ciclov  *************************/

    tmpchar[0]=base_line[baselinecounter];
    if(strcmp(tmpchar,")") && strcmp(tmpchar,"[") && strcmp(tmpchar,"]") && strcmp(tmpchar,"("))
    {
     out<<"NO";
     return;
    }
    if (!strcmp(tmpchar,"(")||!strcmp(tmpchar,"["))
    {
      if (postcounter && !precounter)
      {
	for(int i=0; i<precounter; i++) {
	  if (post[i]==')')Insert(result_line, resultlinecounter,'(');
	  if (post[i]==']')Insert(result_line, resultlinecounter,'[');
	}
      }
      result_line[resultlinecounter]=tmpchar[0];
      resultlinecounter++;
      pre[precounter]=tmpchar[0];
      precounter++;
    }
    if (!strcmp(tmpchar,"]")||!strcmp(tmpchar,")"))
    {
      if (precounter && !postcounter) {
	for (int i=0; i<precounter; i++) {
	  if (pre[i]=='(')Insert(result_line, resultlinecounter,')');
	  if (pre[i]=='[')Insert(result_line, resultlinecounter,']');
	}
	resultlinecounter=resultlinecounter+precounter;
	precounter=0;
	pre[0]='\0';
      }
      post[postcounter]=tmpchar[0];
      postcounter++;
    }
    baselinecounter++;
  }
  out<<result_line<<endl;
}