11 9 17 5 12
5 9 17 11 12
5 9 17 11 12
5 9 11 17 12
5 9 11 12 17
Time now
Time before;
selection_sort(v);
Time after;
cout << "Elapsed time = " << after.seconds_from(before)
<< " seconds\n";
n (1/2) n^{2} (5/2) n - 3 1000 500 000 2 497 2000 2 000 000 4 997
void merge_sort(vector<int>& a, int from, int to)
{ if (from == to) return;
int mid = (from + to) / 2;
/* sort the first and second half */
merge_sort(a, from, mid);
merge_sort(a, mid + 1, to);
merge(a, from, mid, to);
}
Merge Sort (mergsort.cpp)
int binary_search(vector<Employee>& v, int from, int to, string n)
{ if (from > to) return -1;
int mid = (from + to) / 2;
if (v[mid].get_name() == n) return mid;
else if (v[mid].get_name() < n)
return binary_search(v, mid + 1, to, n);
else
return binary_search(v, from, mid -1 , n);
}