Added tested code for A5 (n queen) in C++ with sample output, provided by Salvi sir.

Codes/C++/Code-A5 (N-Queen).cpp

@@ -0,0 +1,86 @@
+// Code-A5 (N-Queen)
+
+#include <iostream>
+#include <vector>
+using namespace std;
+
+// Function to print the board
+void printBoard(vector<vector<int>>& board, int n) {
+    for (int i = 0; i < n; i++) {
+        for (int j = 0; j < n; j++)
+            cout << board[i][j] << " ";
+        cout << endl;
+    }
+    cout << endl;
+}
+
+// Function to check if placing a queen is safe
+bool isSafe(vector<vector<int>>& board, int row, int col, int n) {
+    // Check column
+    for (int i = 0; i < row; i++)
+        if (board[i][col]) return false;
+
+    // Check upper left diagonal
+    for (int i = row - 1, j = col - 1; i >= 0 && j >= 0; i--, j--)
+        if (board[i][j]) return false;
+
+    // Check upper right diagonal
+    for (int i = row - 1, j = col + 1; i >= 0 && j < n; i--, j++)
+        if (board[i][j]) return false;
+
+    return true;
+}
+
+// Backtracking function
+bool solveNQueens(vector<vector<int>>& board, int row, int n) {
+    if (row == n) {
+        printBoard(board, n); // Print one valid arrangement
+        return true;
+    }
+
+    for (int col = 0; col < n; col++) {
+        if (isSafe(board, row, col, n)) {
+            board[row][col] = 1; // Place queen
+            solveNQueens(board, row + 1, n);
+            board[row][col] = 0; // Backtrack
+        }
+    }
+    return false;
+}
+
+int main() {
+    int n, firstRow, firstCol;
+    cout << "Enter size of board (N): ";
+    cin >> n;
+
+    vector<vector<int>> board(n, vector<int>(n, 0));
+
+    cout << "Enter position of first queen (row and column index starting from 0): ";
+    cin >> firstRow >> firstCol;
+
+    // Place first queen
+    board[firstRow][firstCol] = 1;
+
+    cout << "\nAll possible solutions:\n";
+    solveNQueens(board, 0, n); // Start solving from row 0
+
+    return 0;
+}
+
+// SAMPLE OUTPUT
+/*
+* $ ./a.out 
+* Enter size of board (N): 4
+* Enter position of first queen (row and column index starting from 0): 0 0
+* 
+* All possible solutions:
+* 0 1 0 0 
+* 0 0 0 1 
+* 1 0 0 0 
+* 0 0 1 0 
+* 
+* 0 0 1 0 
+* 1 0 0 0 
+* 0 0 0 1 
+* 0 1 0 0 
+*/