```
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int main(){
ll l,r;
cin >> l >> r;
for(int i = l ;i <= r;i++){
cout << i << " ";
}
return 0;
}
```
# Loop
## Idea
We can use a for loop to iterate over all numbers from $l$ to $r$ and print it in $O(r - l)$.
## Code
```
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int MOD = 1E9 + 7;
const int INF = 1E9; const ll INFLL = 1E18;
int l; int r;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> l >> r;
for(int i = l; i <= r; i++) {
cout << i << "\n";
}
}
```