C++ STL - Vector in Reverse Order
Last Updated :
02 Nov, 2022
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Prerequisite: Vectors in C++
A vector can be printed in reverse order with the following methods:
- By traversing in the backward direction using indexing
- By traversing in the backward direction using begin() and end() functions in C++ STL
- By traversing in the backward direction using rbegin() and rend() functions in C++ STL
Examples:
Input: vector = {1, 2, 3, 4, 5}
Output: {5, 4, 3, 2, 1}
Input: vector = {10,5,20,15,25}
Output: {25, 15, 20, 5, 10}1. Traversing the vector in a backward direction using indexing
// C++ STL program to print all elements
// of a vector in reverse order
#include <iostream>
#include <vector>
using namespace std;
int main()
{
vector<int> vec;
vec.push_back(1);
vec.push_back(2);
vec.push_back(3);
vec.push_back(4);
vec.push_back(5);
// Printing original order
cout << "Elements of vector in original order : ";
for (int i : vec) {
cout << i << " ";
}
cout << endl;
// Printing all elements in reverse order
cout << "Elements of vector in reverse order : ";
for (int i = vec.size() - 1; i >= 0; i--)
cout << vec[i] << " ";
return 0;
}
// C++ STL program to print all elements// of a vector in reverse orderusing namespace std;int main(){ vector<int> vec; vec.push_back(1); vec.push_back(2); vec.push_back(3); vec.push_back(4); vec.push_back(5); // Printing original order cout << "Elements of vector in original order : "; for (int i : vec) { cout << i << " "; } cout << endl; // Printing all elements in reverse order cout << "Elements of vector in reverse order : "; for (int i = vec.size() - 1; i >= 0; i--) cout << vec[i] << " "; return 0;}Output
Elements of vector in original order : 1 2 3 4 5 Elements of vector in reverse order : 5 4 3 2 1
2. Using begin() and end() functions
// C++ STL program to print all elements
// of a vector in reverse order
#include <iostream>
#include <vector>
using namespace std;
int main()
{
vector<int> vec;
vec.push_back(1);
vec.push_back(2);
vec.push_back(3);
vec.push_back(4);
vec.push_back(5);
// Printing original order
cout << "Elements of vector in original order : ";
for (int i : vec) {
cout << i << " ";
}
cout << endl;
// Printing all elements in reverse order
cout << "Elements of vector in reverse order : ";
for (auto it = vec.end() - 1; it >= vec.begin(); it--)
cout << *it << " ";
return 0;
}
// C++ STL program to print all elements// of a vector in reverse orderusing namespace std;int main(){ vector<int> vec; vec.push_back(1); vec.push_back(2); vec.push_back(3); vec.push_back(4); vec.push_back(5); // Printing original order cout << "Elements of vector in original order : "; for (int i : vec) { cout << i << " "; } cout << endl; // Printing all elements in reverse order cout << "Elements of vector in reverse order : "; for (auto it = vec.end() - 1; it >= vec.begin(); it--) cout << *it << " "; return 0;}Output
Elements of vector in original order : 1 2 3 4 5 Elements of vector in reverse order : 5 4 3 2 1
3. Using rbegin() and rend() function
// C++ STL program to print all elements
// of a vector in reverse order
#include <iostream>
#include <vector>
using namespace std;
int main()
{
vector<int> vec;
vec.push_back(1);
vec.push_back(2);
vec.push_back(3);
vec.push_back(4);
vec.push_back(5);
// Printing original order
cout << "Elements of vector in original order : ";
for (int i : vec) {
cout << i << " ";
}
cout << endl;
// Printing all elements in reverse order
cout << "Elements of vector in reverse order : ";
for (auto it = vec.rbegin(); it != vec.rend(); it++) {
cout << *it << " ";
}
return 0;
}
// C++ STL program to print all elements// of a vector in reverse orderusing namespace std;int main(){ vector<int> vec; vec.push_back(1); vec.push_back(2); vec.push_back(3); vec.push_back(4); vec.push_back(5); // Printing original order cout << "Elements of vector in original order : "; for (int i : vec) { cout << i << " "; } cout << endl; // Printing all elements in reverse order cout << "Elements of vector in reverse order : "; for (auto it = vec.rbegin(); it != vec.rend(); it++) { cout << *it << " "; } return 0;}Output
Elements of vector in original order : 1 2 3 4 5 Elements of vector in reverse order : 5 4 3 2 1
