I was trying this question

and for some reason that i dont understand my code doesn't work that is following.

```
int rec(int n, vector<int>&v){
if(n == 0){
return 1;
}
if(v[n] != -1){
return v[n];
}
return v[n] = rec(floor(n/2),v) + rec(floor(n/3),v);
}
void solve() {
read(n);
vector<int>v(n+1,-1);
cout<<rec(n,v)<<endl;
}
```

but the following code which has the same logic works.

```
map<ll, ll> mp;
ll calc(ll x) {
if (x == 0)return 1;
if (mp.find(x) != mp.end())return mp[x];
ll res = calc(x / 2) + calc(x / 3);
return mp[x] = res;
}
void solve() {
ll n; cin >> n;
cout << calc(n) << "\n";
}
```