leaders in array.cpp

/*
///////////////////////////////////////////
//Question/Info

Leaders in an array
Easy Accuracy: 49.96% Submissions: 54409 Points: 2
Given an array A of positive integers. Your task is to find the leaders in the array. An element of array is leader if it is greater than or equal to all the elements to its right side. The rightmost element is always a leader.



Example 1:

Input:
n = 6
A[] = {16,17,4,3,5,2}
Output: 17 5 2
Explanation: The first leader is 17
as it is greater than all the elements
to its right.  Similarly, the next
leader is 5. The right most element
is always a leader so it is also
included.


Example 2:

Input:
n = 5
A[] = {1,2,3,4,0}
Output: 4 0


Your Task:
You don't need to read input or print anything. The task is to complete the function leader() which takes array A and n as input parameters and returns an array of leaders in order of their appearance.



Expected Time Complexity: O(n)
Expected Auxiliary Space: O(n)



Constraints:
1 <= n <= 107
0 <= Ai <= 107

Company Tags
 Payu

author: srj_v
///////////////////////////////////////////
*/

#include <bits/stdc++.h>
using namespace std;

// #define int 		   long long int
#define sbit(x) 	   __builtin_popcount(x)
#define pb(x) 		   push_back(x)
#define mp(x,y) 	   make_pair(x,y)
#define eb(x) 		   emplace_back(x)
#define ct(x) 		   cout << x << "\n";
#define ct2(x,y) 	   cout << x << " " << y << "\n";
#define tc(x) 		   cout << x << " ";
#define tc2(x,y) 	   cout << x << " " << y << " ";
#define forn(i,n) 	   for(int i = 0; i < (int)(n); ++i)
#define forx(i,x,n)    for(int i = x; i < (int)(n); ++i)
#define nfor(i,n)      for(int i = n-1; i >= 0; --i)
#define all(v) 		   v.begin(),v.end()
#define fsp(x,y)       fixed << setprecision(y) << x
#define PI 			   3.1415926535897932384626433832795
#define MOD 		   1000000007 // (1e9+7)
#define pii 		   pair<int,int>
#define pis 		   pair<int,string>
#define vi  		   vector<int>
#define vii 		   vector<pii>
#define mii 		   map<int,int>
#define p_q            priority_queue // priority_queue<int> (&) priority_queue< int,vi,greater<int> >
#define _IOS      	   ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

typedef long double ld;
typedef long long int lli;

#pragma GCC optimize("Ofast")

void c_p_c()
{
#ifndef ONLINE_JUDGE
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
#endif
}


int32_t main() {
///////////
	c_p_c();
///////////
	_IOS
//////////

	// code

	/*
	int t ; cin >> t; while(t--){}
	*/



	class Solution {
		//Function to find the leaders in the array.
	public:
		vector<int> leaders(int a[], int n) {
			// Code here

			vector<int> v;

			int max = a[n - 1];
			v.push_back(max);
			for (int i = n - 2; i >= 0 ; i--) {

				if (a[i] >= max) {
					max = a[i];
					v.push_back(max);
				}

			}

			reverse(v.begin(), v.end());
			return v;

		}
	};



// cerr << "time: " << clock() << " ms" << '\n';
	return 0;
}