import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }

string COLOR(string s = "") { return "\x1b[" ~ s ~ "m"; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }




void main() {
  try {
    for (; ; ) {
      const N = readInt;
      auto A = new int[N];
      auto B = new int[N];
      foreach (u; 0 .. N) {
        A[u] = readInt;
        B[u] = readInt;
      }
      
      auto nxt = new int[N + 1];
      nxt[N] = N;
      foreach_reverse (u; 0 .. N) {
        nxt[u] = (B[u] == 1) ? u : nxt[u + 1];
      }
      
      auto graph = new int[][N];
      foreach (u; 0 .. N) {
        if (A[u] == 1) {
          graph[u + 1] ~= u;
        } else if (B[u] == 2) {
          graph[nxt[u]] ~= u;
        }
      }
      auto indeg = new int[N];
      foreach (u; 0 .. N) foreach (v; graph[u]) ++indeg[v];
      debug writeln("graph = ", graph);
      
      int[] ans;
      void dfs(int u) {
        ans ~= u;
        foreach (v; graph[u]) dfs(v);
      }
      foreach (u; 0 .. N) if (!indeg[u]) dfs(u);
      
      foreach (u; ans) writeln(u + 1);
      debug writeln("========");
    }
  } catch (EOFException e) {
  }
}