Biggest monotonic subsequence

#include <iostream>
#include <vector>

using namespace std;

pair<int, int> BiggestIncreasingSubs(const vector<int>& arr){
    int l = -1;
    int r = -1;
    int biggest_len = 0;
    int cur_l = 0;
    for (int i = 0; i < arr.size() - 1; ++i){
        if (arr[i] > arr[i+1]){
            if (i - cur_l + 1 > biggest_len){
                l = cur_l;
                r = i;
                biggest_len = i - cur_l + 1;
            }
            cur_l = i + 1;
        }
    }
    if (arr.size() - cur_l > biggest_len){
        l = cur_l;
        r = arr.size() - 1;
    }
    return {l, r};
}

int main() {
    int n;
    cin >> n;
    vector<int> v(n);
    for (int i = 0; i < n; ++i) {
        cin >> v[i];
    }
    auto ans1 = BiggestIncreasingSubs(v);
    reverse(v.begin(), v.end());
    auto ans2 = BiggestIncreasingSubs(v);
    if (ans1.second - ans1.first > ans2.second - ans1.first){
        cout << ans1.first << " " << ans1.second;
    } else {
        cout << v.size() - 1 - ans2.second << " " << v.size() - ans1.first - 1;
    }
    return 0;
}