int minimumDistances(vector<int> a) {
unordered_set <int> c;
for(int i(0); i<a.size();++i){
    for(int j(i+1);j<a.size();++j){
        if(a[i]==a[j]){
        c.insert(i);
        c.insert(j);
        }
    }
}
for(auto x: c){
    cout << x << " ";
}
cout << endl;
int min(999);
for(int i(0); i<a.size();++i){
    for(int j(i+1);j<a.size();++j){
        auto at = find(c.begin(), c.end(), i);
        auto bt = find(c.end(), c.end(), j);
        if(at==c.end()||bt==c.end()){
         cout << "i :" << i << " j :" << j <<endl;
        }
        if(at!=c.end()&&bt!=c.end()&&a[i]!=a[j]) {
            if(abs(i-j)<min){
                min = abs(i-j);
            }
        }
    }
}

return min;
}