Lungime bara repere [C++][Bkt]

#include <iostream>
#include <fstream>
using namespace std;

int L, n;
int a[100]; //Vectorul cu repere
int v[100]; //Vectorul solutiei

void afis(int k){
    static int nr = 1;
    cout << "\nSolutia #" << nr++ << " : ";
    for(int i = 1; i <= k;i++) cout << v[i] << " ";
}

void backt(int lung, int k){
    for (int i=1; i <=n;i++){
        v[k] = a[i];
        lung += a[i];
        if(lung == L) afis(k);
        else if (lung < L) backt(lung,k+1);
        lung -= a[i];
        }
}

int main()
{
    ifstream in("date.txt");
    in >> L >> n;
    for (int i=1;i<=n;i++) in >> a[i];

    backt(0,1);
}