import java.io.*;
import java.util.*;

public class SegTreeImp{
    public static int[] segTreeArr;
    public static int n;
    public static void main (String[] args)throws IOException{
        Scanner in = new Scanner (new FileReader("input"));
        n = in.nextInt();
        int q = in.nextInt();
        int[] arr = new int[n];
        for (int i = 0; i < n; i++){
            arr[i] = in.nextInt();
        }
        segTreeArr = new int[nextPowerTwo(n)];
        //System.out.println('\n'+nextPowerTwo(n));
        for (int i = 0; i < arr.length; i++){
            segTreeArr[n+i] = arr[i];
        }

        for (int i = n-1; i >= 1; i--){
            segTreeArr[i] = segTreeArr[i*2]+segTreeArr[i*2+1];
        }
        System.out.println(Arrays.toString(segTreeArr));
        System.out.println(intervalSum(1, 0, 1, 0, 7));

    }

    public static void pointUpdate(int updateIndex, int updatePlus){
        updateIndex += n;
        segTreeArr[updateIndex] += updatePlus;
        updateIndex/=2;
        while (updateIndex >= 1){
            segTreeArr[updateIndex] = segTreeArr[updateIndex*2]+segTreeArr[updateIndex*2+1];
            updateIndex /= 2;
        }
    }

    public static int intervalSum(int node, int queryStart, int queryEnd, int nodeStart, int nodeEnd){
        if (queryStart <= nodeStart && nodeEnd <= queryEnd){//current interval is fully within query interval
            return segTreeArr[node];
        }

        if (queryEnd < nodeStart || queryStart > nodeEnd){//current interval is disjoint
            return 0;
        }

        return (intervalSum(node*2, queryStart, queryEnd, nodeStart, nodeEnd/2))
                + intervalSum(node*2+1, queryStart, queryEnd, nodeEnd/2+1, nodeEnd);

    }
    static int nextPowerTwo(int n){
        n++;
        int count = 0;

        // First n in the below
        // condition is for the
        // case where n is 0
        if (n > 0 && (n & (n - 1)) == 0)
            return n;

        while(n != 0)
        {
            n >>= 1;
            count += 1;
        }

        return 1 << count;
    }
}