/* Subject: Contest submission for problem #1, file 1.java */
/* kelvinso@imail.EECS.Berkeley.EDU */
/* Thu Sep 18 02:52:36 PDT 2003 */
/*___CONTEST_SUBMISSION___ kelvinso 1 */
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.BufferedReader;
import java.io.StreamTokenizer;
import java.util.*;
import java.lang.Double;


class P1 {

    public static void main(String[] arg) throws Exception{
	
	BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
	String string;
	boolean newLine = true;
	boolean afterColon = false;
	boolean inFunction = false;
	boolean afterAssignment = false;
	boolean openPara = false;
	boolean closePara = false;
	boolean isGoto = false;
	boolean isI = false;
	boolean isF = false;
	int numBegin = 0;
	int gotoNumIndex = 0;
	Instruction inst = new Instruction();
	ArrayList set = new ArrayList();
	int setIndex = 0;
	ArrayList instructions = new ArrayList();
	int indexInst = 0;
		
	while ((string = in.readLine()) != null) {
	    for (int i = 0; i<string.length(); i++) {
		if(string.charAt(i) == ';') {
		    if(isGoto)
			inst.gotoLine = (new Integer(string.substring(gotoNumIndex, i))).intValue();
		    //System.out.println(inst);
		    newLine = true;
		    isGoto = false;
		    afterColon = false;
		    inFunction = false;
		    afterAssignment = false;
		    openPara = false;
		    closePara = false;
		    isI = false;
		    isF = false;
		    gotoNumIndex = 0;
		    continue;
		}
		if(string.charAt(i) == ':') {
		    int indexInt = (new Integer(string.substring(numBegin, i))).intValue();
		    if(indexInt == 0){
			instructions = new ArrayList();
			set.add(setIndex, instructions);
			setIndex ++;
			indexInst = 0;
		    }

		    inst = new Instruction();
		    inst.index = indexInt;
		    instructions.add(indexInst, inst);

		    inst.index = indexInst;
		    indexInst++;
		    	
		    afterColon = true;
		    continue;
		}
		if(string.charAt(i) == '=') {
		    afterAssignment = true;
		    continue;
		}

		if(newLine && '0'<= string.charAt(i) && string.charAt(i) <= '9') {
		    newLine = false;
		    numBegin = i;
		    continue;
		}
		
		if(afterColon && !afterAssignment && string.charAt(i) == 's' 
		   && string.charAt(i+1) == 't' && string.charAt(i+2) == 'o'
		   && string.charAt(i+3) == 'p') {
		    inst.stop = true;
		    i += 3;
		    continue;
		}
		
		if(afterColon && !afterAssignment && string.charAt(i) == 'i') {
		    if(string.charAt(i+2) == '=') {
			inst.assignedChar.add(new Character(string.charAt(i)));
		    } else {
			isI = true;
		    }
		    continue;
		}
		
		if(afterColon && !afterAssignment && isI && string.charAt(i) == 'f') {
		    isF = true;
		    afterAssignment = true;
		    inst.ifStatement = true;
		    continue;
		}
		
		if(afterColon && !afterAssignment && string.charAt(i) != ' ') {
		    inst.assignedChar.add(new Character(string.charAt(i)));
		    continue;
		}
		
		if(afterAssignment && string.charAt(i) == '(') {
		    openPara = true;
		    continue;
		}
		
		if(afterAssignment && string.charAt(i) == ')') {
		    closePara = true;
		    continue;
		}
		
		if(openPara && !closePara && string.charAt(i) != ',' && string.charAt(i) != ' ') {
		    inst.usedChar.add(new Character(string.charAt(i)));
		    continue;
		}
		
		if(openPara && closePara && string.charAt(i) == 'g'
		   && string.charAt(i+1) == 'o' && string.charAt(i+2) == 't'
		   && string.charAt(i+3) == 'o') {
		    isGoto = true;
		    i += 4;
		}
		
		if(isGoto &&'0' <= string.charAt(i) && '9' >= string.charAt(i)
		   && gotoNumIndex == 0) {
		    gotoNumIndex = i;
		}
	    }
	}
	
	for(int i = 0; i< set.size(); i++) {
	    ArrayList ins = (ArrayList) set.get(i);
	    //System.out.println(ins);
	}

	for(int i = 0; i < set.size(); i++) {
	    ArrayList ins = (ArrayList) set.get(i);
	    if(findUndefined(ins, 0))
		System.out.println("Set " + i + ": No use before definition");
	    else
		System.out.println("Set " + i + ": Possible use before definition");
	}
    }

    public static boolean findUndefined(ArrayList instructions, int index) {
	Instruction inst = (Instruction) instructions.get(index);
	//System.out.println(inst);
	if(inst.stop)
	    return true;
	if(inst.path.contains(new Integer(index)))
	    return true;
	HashSet defined = new HashSet();
	defined.addAll(inst.definedChar);
	if(!defined.containsAll(inst.usedChar))
	    return false;
	defined.addAll(inst.assignedChar);

	if(inst.ifStatement) {
	    Instruction gotoInst = (Instruction) instructions.get(inst.gotoLine);
	    gotoInst.path.add(new Integer(index));
	    gotoInst.path.addAll(inst.path);
	    gotoInst.definedChar.addAll(defined);
	    if(!findUndefined(instructions, inst.gotoLine))
		return false;
	}
	
	Instruction nextInst = (Instruction) instructions.get(index + 1);
	nextInst.path.add(new Integer(index));
	nextInst.path.addAll(inst.path);
	nextInst.definedChar.addAll(defined);
	if(!findUndefined(instructions, index + 1))
	    return false;

	inst.path.clear();
	inst.definedChar.clear();
	return true;
    }
}

class Instruction {
    
    public int index;
    public boolean ifStatement = false;
    public HashSet assignedChar = new HashSet();
    public HashSet usedChar = new HashSet();
    public int gotoLine;
    public boolean stop = false;
    public HashSet path = new HashSet();
    public HashSet definedChar = new HashSet();

    public Instruction() {
    }

    public String toString() {
	return "index: " + index + " ifStatement: " + ifStatement + " assignedChar: " + assignedChar + " usedChar: " + usedChar + " gotoLine: " + gotoLine + " stop: " + stop + " path: " + path + " definedChar: " + definedChar;
    }

}