Minimizing the dot product codechef in c++

Here is an example implementation in C++ for minimizing the dot product, along with explanations for each step:

#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

int main() {
    int t;
    cin >> t; // Input the number of test cases

    while (t--) {
        int n;
        cin >> n; // Input the size of the arrays

        vector<int> a(n), b(n);

        for (int i = 0; i < n; i++) {
            cin >> a[i]; // Input elements of array a
        }

        for (int i = 0; i < n; i++) {
            cin >> b[i]; // Input elements of array b
        }

        sort(a.begin(), a.end()); // Sort array a in ascending order
        sort(b.begin(), b.end(), greater<int>()); // Sort array b in descending order

        long long dotProduct = 0;

        for (int i = 0; i < n; i++) {
            dotProduct += (long long)a[i] * b[i]; // Calculate the dot product
        }

        cout << dotProduct << endl; // Output the minimized dot product
    }

    return 0;
}

Explanation for each step:

1. Include necessary header files: <iostream> for input/output, <algorithm> for sorting, and <vector> for using vectors.
2. Use the using namespace std; directive to avoid having to write std:: before standard library functions.
3. Declare the main() function, which is the entry point of the program.
4. Read the number of test cases t from the user.
5. Start a loop that runs t times, to handle multiple test cases.
6. Read the size of the arrays n from the user.
7. Create two vectors a and b of size n to store the elements of the arrays.
8. Use a loop to read the elements of array a from the user.
9. Use another loop to read the elements of array b from the user.
10. Sort array a in ascending order using the sort() function from the <algorithm> library.
11. Sort array b in descending order using the sort() function and the greater<int>() comparator.
12. Initialize a variable dotProduct of type long long to store the dot product.
13. Use a loop to calculate the dot product by multiplying the corresponding elements of arrays a and b, and adding the result to dotProduct.
14. Output the minimized dot product by printing the value of dotProduct.
15. Repeat the loop for the remaining test cases.
16. End the main() function and return 0 to indicate successful program execution.

This code takes the size of two arrays as input, sorts them in different orders, calculates the dot product by multiplying corresponding elements, and outputs the minimized dot product.