Given a sorted array, the task is to remove the duplicate elements from the array using STL in C++
Examples:
Input: arr[] = {2, 2, 2, 2, 2} Output: arr[] = {2} Input: arr[] = {1, 2, 2, 3, 4, 4, 4, 5, 5} Output: arr[] = {1, 2, 3, 4, 5}
Approach:
The duplicates of the array can be removed using the unique() function provided in STL.
Below is the implementation of the above approach.
#include <bits/stdc++.h> using namespace std;
// Function to remove duplicate elements void removeDuplicates( int arr[], int n)
{ // Initialise a vector
// to store the array values
// and an iterator
// to traverse this vector
vector< int > v(arr, arr + n);
vector< int >::iterator it;
// using unique() method to remove duplicates
it = unique(v.begin(), v.end());
// resize the new vector
v.resize(distance(v.begin(), it));
// Print the array with duplicates removed
cout << "\nAfter removing duplicates:\n" ;
for (it = v.begin(); it != v.end(); ++it)
cout << *it << ", " ;
cout << '\n' ;
} // Driver code int main()
{ int arr[] = { 1, 2, 2, 3, 4, 4, 4, 5, 5 };
int n = sizeof (arr) / sizeof (arr[0]);
// Print array
cout << "\nBefore removing duplicates:\n" ;
for ( int i = 0; i < n; i++)
cout << arr[i] << " " ;
// call removeDuplicates()
removeDuplicates(arr, n);
return 0;
} |
Output:
Before removing duplicates: 1 2 2 3 4 4 4 5 5 After removing duplicates: 1, 2, 3, 4, 5,