/* Problem statement : we have a vector as an input. task is to A. find out first two maximum numbers B. remove biggest number from vector C. add number to vector which is abdolute difference of two numbers found in step A D. print two numbers found in step A repeat steps A to D three times Query : What is best method to achieve the same ? Method1 or Method 2? i.e. priority_queue or make_heap ? */ #include #include #include #include using namespace std; void print(vector v) { for(auto elem : v) cout << elem << " "; cout << endl << endl; } void Method1(vector v) { int i=3; while(i) { make_heap(v.begin(),v.end()); int int_1 = v.front(); pop_heap(v.begin(),v.end()); v.pop_back(); make_heap(v.begin(),v.end()); int int_2 = v.front(); cout << "Top two elements are : " << int_1 << " "<< int_2 << endl; v.push_back(int_1-int_2); //cout << "Wid sub : "; //print(v); --i; } } void Method2(vector v) { priority_queue q; for(auto elem : v) { q.push(elem); } int i=3; while(i) { int int_1 = q.top(); q.pop(); int int_2 = q.top(); cout << "Top two elements are : " << int_1 << " "<< int_2 << endl; q.push(int_1-int_2); --i; } } int main() { vector v = {2,5,9,1}; cout << "Initial : "; print(v); cout << "*****make_heap method*****" << endl << endl; Method1(v); cout << endl << endl << endl ; cout << "*****priority_queue method*****" << endl << endl; Method2(v); return 0; }

make_heap Vs Priority_Queue