#include <bits/stdc++.h>   using namespace std;   double EPS = 1e-9;   int INF = 2000000000;   long long INFF = 8000000000000000000LL;   double PI = acos(-1);   string IntToString(int a) {     char x[100];     sprintf(x,  %d , a);     string s = x;     return s;   }   int StringToInt(string a) {     char x[100];     strcpy(x, a.c_str());     int res;     sscanf(x,  %d , &res);     return res;   }   int spaces = 0;   char c[5];   int main() {     while (scanf( %c , &c[0]) != EOF && c[0] !=   n ) {       scanf( %c%c , &c[1], &c[2]);       if (c[2] ==  > ) {         spaces += 2;         for (int(i) = (1); (i) <= (spaces - 2); (i)++) printf(   );         for (int(i) = (0); (i) <= (2); (i)++) printf( %c , c[i]);         puts(  );       } else {         scanf( %c , &c[3]);         spaces -= 2;         for (int(i) = (1); (i) <= (spaces); (i)++) printf(   );         for (int(i) = (0); (i) <= (3); (i)++) printf( %c , c[i]);         puts(  );       }     }     return 0;   }   