#include <stdio.h>
#include <string.h>
int main(int c,char *v[]){
 for(int i=0;i<4;i++)
  fputc(v[1][i],stdout);
 FILE* p=fopen("TapTinTau.txt","r");
 fseek(p,0,SEEK_END);
 long int f=0;
 long int g=ftell(p)/71;
 //printf("%ld\n",g);
 long int m;
 char e;
 do{
  fseek(p,f*71+6,SEEK_SET);
  for(int j=0;j<strlen(v[1]);j++)
   if(v[1][j]<fgetc(p)){
    fflush(stdout);
    fclose(p);
    return 0;}
  fseek(p,g*71+6,SEEK_SET);
  for(int j=0;j<strlen(v[1]);j++)
   if(v[1][j]>fgetc(p)){
    fflush(stdout);
    fclose(p);
    return 0;}
  m=(f+g)/2;
  fseek(p,m*71+6,SEEK_SET);
  int t=0;
  for(int j=0;j<strlen(v[1]);j++){
   if(v[1][j]<fgetc(p)){
    g=m;
    t=1;
    break;}
   if(v[1][j]>fgetc(p)){
    f=m;
    t=1;
    break;}}
  if(t==0){
   printf("%ld",m);
   break;}}
 while(f<g);
 fseek(p,g*71,SEEK_SET);
 for(int i=0;i<6;i++)
  printf("%c",v[1][i]);
 fflush(stdout);
 fclose(p);}