#include <iostream>
#include <vector>

using namespace std;

bool next_combination(vector<int> &a, int n) {
    for (int i = a.size() - 1; i >= 0; i--)
        if (a[i] < n - a.size() + i + 1) {
            a[i]++;
            for (int j = i + 1; j < a.size(); j++)
                a[j] = a[j - 1] + 1;
            return true;
        }
    return false;
}