Difference in execution time in C and C++

Question

I recently found this site called codechef, where you can submit solutions to problems. I had submitted two answers for a question, one in C and the other in C++. Both codes

Answer 1

The code is not really the same even though they do the same thing

The c++ version uses cin and streams which are slower than scanf etc by default.

By default, cin/cout waste time synchronizing themselves with the C library’s stdio buffers, so that you can freely intermix calls to scanf/printf with operations on cin/cout. You can turn this off with std::ios_base::sync_with_stdio(false);

By doing this the time taken will more or less be similar I would expect

Answer 2

I usually add these 3 lines in my code just after the main() for faster input output :

ios_base::sync_with_stdio(false);

cin.tie(NULL);

cout.tie(NULL);

So , Try this :

int main()  
{
   ios_base::sync_with_stdio(false);
   cin.tie(NULL);
   cout.tie(NULL);
   int n, k, t,num=0;
   cin>>n>>k;
   for(int i=0;i<n;i++)  {
     cin>>t;
     if(t%k==0)  num++;
   }

   cout<<num;
   return 0;
 }