HaltProblem.java

package my.ACm.Quera._26_sathe_2;

import java.util.HashMap;

import java.util.Scanner;

public class HaltProblem {

    public static final int mod = 10*10*10*10*10*10*10*10*10 + 7;

    private static String cmdOUT = "";

    private static HashMap<String, Integer> vars = new HashMap<>();

    public static void main(String[] args) {

            Scanner sc = new Scanner(System.in);

            int n = sc.nextInt();

            String[] lines = new String[n];

            sc.nextLine(); // cleare buffer

            boolean linesNumber[] = new boolean[n];

            for (int i = 0; i < n; i++)

                lines[i] = sc.nextLine();

            int pointer = 0;

            boolean flag = false;

            while (pointer < n) {

                if (linesNumber[pointer]) {

                    System.out.println(-1);

                    System.exit(1);

                }

                linesNumber[pointer] = true;

                String[] nowLine = lines[pointer].split(" ");

                if (nowLine.length == 2) {

                    if (nowLine[0].equals("cout")) {

                        cout(nowLine[1]);

                    } else {

                        pointer = goTo(nowLine[1]);

                        flag = true;

                    }

                } else {

                    assign(nowLine);

                }

                if (!flag)

                    pointer++;

                flag = false;

            }

            System.out.println(cmdOUT.trim());

    }

    private static void assign(String[] nowLine) {

        // 1 ,   3 , 5

        int a = vars.containsKey(nowLine[3]) ? vars.get(nowLine[3]) : Integer.valueOf(nowLine[3]), b = vars.containsKey(nowLine[5]) ? vars.get(nowLine[5]) : Integer.valueOf(nowLine[5]);

        int sum = a + b;

        vars.put(nowLine[1], sum % mod);

    }

    private static int goTo(String key) {

        int pointer;

        if (vars.containsKey(key)) {

            pointer = Integer.valueOf(vars.get(key));

        } else {

            pointer = Integer.valueOf(key);

        }

        return pointer - 1;

    }

    private static void cout(String key) {

        if (vars.containsKey(key))

            cmdOUT += (vars.get(key)) + "\n";

        else

            cmdOUT += ((key)) + "\n";

    }

}