import java.io.*;

public class ST1 extends Thread {
        static boolean useSynchronize=false;
        static String datafile;
        static int sum1=0;
        static int sum2=0;
        private int numThreads, myNum;
        private BufferedReader br;
        private ST1(int numThreads, int myNum) throws IOException {
                this.numThreads = numThreads;
                this.myNum = myNum;
                br = new BufferedReader(new InputStreamReader(new FileInputStream(datafile)));
        }
        public void run() {
                try {
                        String line = br.readLine();
                        int mysum = 0;
                        int count=0;
                        while (line!=null) {
                                if (count%numThreads==myNum) {
                                        if (useSynchronize) {
                                                synchronized(datafile) {
                                                        sum1 += Integer.parseInt(line.trim());
                                                }
                                        } else
                                                sum1 += Integer.parseInt(line.trim());
                                        mysum += Integer.parseInt(line.trim());
                                }
                                count++;
                                System.out.print(myNum);
                                if (count%50==0) System.out.println();
                                line = br.readLine();
                        }
                        sum2 += mysum;
                } catch (IOException ioe) {System.out.println("IO Exception in thread "+Thread.currentThread().getName()); }
        }
        public static void main(String[] a) throws Exception {
                int n = Integer.parseInt(a[0]);
                datafile = a[1];
                useSynchronize = a.length>2;
                ST1[] st = new ST1[n];
                for (int i=0; i<n; i++)
                        st[i] = new ST1(n,i);
                for (int i=0; i<n; i++)
                        st[i].start();
                for (int i=0; i<n; i++)
                        st[i].join();
                System.err.println("\n\nsum1 = "+sum1);
                System.err.println("sum2 = "+sum2);
        }
}