Revers_an_Array.cpp

/*

Reverse an Array

You are given an array of integers arr[]. Your task is to reverse the given array.

Examples:

Input: arr = [1, 4, 3, 2, 6, 5]
Output: [5, 6, 2, 3, 4, 1]
Explanation: The elements of the array are 1 4 3 2 6 5. After reversing the array, the first element goes to the last position, the second element goes to the second last position and so on. Hence, the answer is 5 6 2 3 4 1.

Input: arr = [4, 5, 2]
Output: [2, 5, 4]
Explanation: The elements of the array are 4 5 2. The reversed array will be 2 5 4.

Input: arr = [1]
Output: [1]
Explanation: The array has only single element, hence the reversed array is same as the original.

Constraints:
1<=arr.size()<=105
0<=arr[i]<=105

*/

#include <bits/stdc++.h>

using namespace std;

class Solution {
public:
    void reverseArray(vector<int>& arr) {
        int n = arr.size();
        int j = 0;
        vector<int> arr1(n);

        for (int i = n - 1; i >= 0; i--) {
            arr1[j] = arr[i];
            j++;
        }

        for (int j = 0; j < n; j++) {
            arr[j] = arr1[j];
        }
    }
};

int main() {
    int t;
    cin >> t;
    cin.ignore();

    while (t--) {
        vector<int> arr;
        string input;
        getline(cin, input);

        stringstream ss(input);
        int number;

        while (ss >> number) {
            arr.push_back(number);
        }

        Solution ob;
        ob.reverseArray(arr);

        for (int i = 0; i < arr.size(); i++) {
            cout << arr[i] << " ";
        }
        cout << endl;
    }
    cout << "~" << endl;

    return 0;
}