#include <bits/stdc++.h>
using namespace std;
long long A[15000];        
long long arb[60000];     
void construieste(int st, int dr, int nod) {
    if (st == dr) {
        arb[nod] = A[st];
        return; }
        
    int mij = (st + dr) / 2;
    construieste(st, mij, 2 * nod);
    construieste(mij + 1, dr, 2 * nod + 1);

    arb[nod] = arb[2 * nod] + arb[2 * nod + 1];}

int main() {
    ifstream cin("datorii.in");
    ofstream cout("datorii.out");

    int N, M;
    cin >> N >> M;

    for (int i = 1; i <= N; i++)
        cin >> A[i];

    construieste(1, N, 1);

    return 0;}