I was trying to submit this -> Remove Max Number of Edges to Keep Graph Fully Traversable question.

but I got TLE because of sort using rbegin

sort( edges.rbegin(), edges.rend())

but after change with comparator funtction code got accepted.

sort(edges.begin(), edges.end(), [&](vector <int> &a, vector <int> &b){
            return a[0] > b[0];
        });

Submission Using rbegin

Submission Using comparator

I tried to run this in local and got similar performance but when I used some different build command I got 2x time difference.

Build command: g++ a.cpp

Following  code I used for benchmarking.  

<details open>
<summary> Benchmarking code</summary>

int n; cin >> n; srand(time(0)); vector ans(n);

for(int i = 0; i < n; ++i){ ans[i] = random() % 100000; }

vector xyz = ans;

const clock_t begin_time = clock();

sort(ans.begin(), ans.end(), greater ());

std::cout << float( clock () — begin_time ) / CLOCKS_PER_SEC << endl;

const clock_t begin_time2 = clock(); sort(xyz.rbegin(), xyz.rend());

std::cout << float( clock () — begin_time2 ) / CLOCKS_PER_SEC << endl; ```

I think that leetcode is using similar build command to execute the program. Can anyone explain why this time difference happening?