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#include <iostream>
#include <fstream>
#include <vector>
#include <map>
#include <cstring>
#include <queue>
#include <algorithm>
//#include <bits/stdc++.h>
//#include "molecules.h"
using namespace std;

struct node {
    int idx, at, weight;
    node(int _idx, int _at, int _weight){
        idx = _idx;
        at = _at;
        weight = _weight;
    }
};
int dp[10005][1005];
node backtrac[10005][1005];
vector<int> v;
int rec(int at, int weight) {
    if(weight == 0) {
        backtrac[at][weight].at = -1;
        backtrac[at][weight].weight = -1;
        backtrac[at][weight].idx = -1;
        
        return 1;
    }
    if(at == -1) {
        return 0;
    }
    if(dp[at][weight] != -1) {
        return dp[at][weight];
    }
    int result = 0;
    int r1 = 0, r2 = 0;
    if(weight - v[at] >= 0) {
        r1 = rec(at - 1, weight - v[at]);
    }
    r2 =  rec(at - 1, weight);
    
    if(r1 > r2) {
        backtrac[at][weight].idx = at;
        backtrac[at][weight].weight = weight - v[at];
        backtrac[at][weight].at = at - 1;
        
        
    }
    else {
        backtrac[at][weight].idx = -1;
        backtrac[at][weight].weight = weight - v[at];
        backtrac[at][weight].at = at - 1;
        
    }
    return dp[at][weight] = max(r1, r2);
}
vector<int> find_subset(int l, int u, vector<int> w) {
    v  =w;
    int n = w.size();
    int W = -1;
    memset(dp, -1, sizeof dp);
    for(int i = l; i <= u; i++) {
        if(rec(n - 1, i) == 1) {
            W = i;
            break;
        }
    }
    if(W == -1) {
        return {};
    }
    pair<int, int> at;
    vector<pair<int, int> > res;
    int tmp = 0;
    for(at = make_pair(n - 1, W); at != make_pair(-1, -1); at = backtrac[backtrac[at.first][at.second].first][backtrac[at.first][at.second].second]) {
        res.push_back(make_pair(at.first, at.second));
    }
    vector<int> R;
    for(int i = 0; i< (int) res.size(); i++) {
        if(i + 1 < (int) res.size() and res[i].second != res[i + 1].second) {
            R.push_back(res[i].first + 1);
            cout << res[i].first + 1 << endl;
        }
    }
    return R;
}

int main() {
    ios::sync_with_stdio(0);
    vector<int> v = find_subset(10, 20, {15, 17, 16, 18});
    return 0;
}