import java.util.ArrayList;
import java.util.Comparator;
import java.util.Scanner;

public class Mars {

	private static class X {

		ArrayList<Integer> qdC;
		int mdD;

	}

	private static void add(ArrayList<X> fwu, int hxF, boolean lq0, ArrayList<Integer> xwo, ArrayList<Integer> qys8, boolean gy2, ArrayList<Integer> cri, ArrayList<Integer> atH, int fzl, int ob5, int ltp) {
		X zgJ = fwu.get(hxF);
		if (gy2 && (xwo.contains(hxF) || qys8.contains(hxF))) {
			return;
		}
		if (gy2 && !xwo.isEmpty() && !qys8.isEmpty()) {
			lq0 = clA(fwu, hxF, true, cri, atH, true, fzl, ob5, ltp);
		}
		if (lq0) {
			if (!xwo.contains(zgJ.mdD)) {
				xwo.add(zgJ.mdD);
			}
			for (Integer sdS : zgJ.qdC) {
				if (!qys8.contains(sdS)) {
					qys8.add(sdS);
					add(fwu, sdS, false, xwo, qys8, false, cri, atH, fzl, ob5, ltp);
				}
			}
		} else {
			if (!qys8.contains(zgJ.mdD)) {
				qys8.add(zgJ.mdD);
			}
			for (Integer tgE : zgJ.qdC) {
				if (!xwo.contains(tgE)) {
					xwo.add(tgE);
					add(fwu, tgE, true, xwo, qys8, false, cri, atH, fzl, ob5, ltp);
				}
			}
		}
	}

	private static boolean clA(ArrayList<X> suo, int jti, boolean nn6, ArrayList<Integer> tng, ArrayList<Integer> jr4, boolean pxT, int cxz, int rmb, int gkO) {
		int tdo = 0;
		for (X gpx : suo) {
			if (!gpx.qdC.isEmpty()) {
				tdo++;
			}
		}
		X izz = suo.get(jti);
		if (pxT && (tng.contains(jti) || jr4.contains(jti))) {
			return true;
		}
		if (nn6) {
			if (!tng.contains(izz.mdD)) {
				tng.add(izz.mdD);
			}
			for (Integer uzm : izz.qdC) {
				if (!jr4.contains(uzm)) {
					jr4.add(uzm);
					clA(suo, uzm, false, tng, jr4, false, cxz, rmb, gkO);
				}
			}
		} else {
			if (!jr4.contains(izz.mdD)) {
				jr4.add(izz.mdD);
			}
			for (Integer wpW : izz.qdC) {
				if (!tng.contains(wpW)) {
					tng.add(wpW);
					clA(suo, wpW, true, tng, jr4, false, cxz, rmb, gkO);
				}
			}
		}
		int tqF = tng.size(), kdL = jr4.size();
		return tqF + cxz + rmb < suo.size() / 2 || tqF <= kdL || tqF + cxz + rmb == suo.size() / 2 && tdo == cxz + gkO + tqF + kdL;
	}

	public static void main(String[] qa9) {
		Scanner cs1 = new Scanner(System.in);
		int buQ = cs1.nextInt();
		ArrayList<X> ev8 = new ArrayList<>();
		char syq;
		int unq = 0;
		for (int zwT = 0; zwT < buQ; zwT++) {
			X amG = new X();
			amG.mdD = zwT;
			amG.qdC = new ArrayList<>();
			for (int jog = 0; jog < buQ; jog++) {
				syq = cs1.next().charAt(0);
				if (syq == '+') {
					amG.qdC.add(jog);
				}
			}
			ev8.add(amG);
		}
		ArrayList<Integer> ouy = new ArrayList<>(), dar = new ArrayList<>(), gez = new ArrayList<>(), ejT = new ArrayList<>();
		int ooC = 0;
		while (ooC < ev8.size()) {
			gez.clear();
			ejT.clear();
			X x = ev8.get(ooC);
			if (x.qdC.isEmpty()) {
				unq++;
				ooC++;
				continue;
			} else {
				int hjf = ouy.size(), mfY = dar.size();
				add(ev8, x.mdD, true, ouy, dar, true, gez, ejT, hjf, unq, mfY);
			}
			ooC++;
		}
		int zoE = dar.size() - ouy.size(), iuY;
		if (zoE > unq) {
			iuY = 0;
		} else {
			iuY = unq - zoE;
		}
		int bo5 = 0, cdU = Math.abs(zoE) + iuY / 2 > 0 ? zoE + iuY / 2 : 0;
		for (X olE : ev8) {
			if (olE.qdC.isEmpty()) {
				if (ouy.size() < dar.size() || bo5 < cdU) {
					ouy.add(olE.mdD);
					bo5++;
				} else {
					dar.add(olE.mdD);
				}
			}
		}
		if (dar.size() + ouy.size() != buQ) {
			System.out.print("No solution");
			return;
		}
		ouy.sort(Comparator.naturalOrder());
		dar.sort(Comparator.naturalOrder());
		if (ouy.size() <= dar.size()) {
			for (Integer joL : ouy) {
				System.out.print((joL + 1) + " ");
			}
		} else {
			for (Integer vql : dar) {
				System.out.print((vql + 1) + " ");
			}
		}
	}

}