检查给定的数组元素是否可以形成回文矩阵

// C++ program for the above approach
#include <bits/stdc++.h>
using namespace std;
// Function to fill the matrix to
// make it palindromic if possible
void fill(vector<pair<int, int> >& temp,
          priority_queue<pair<int, int> >& q,
          vector<vector<int> >& grid)
{
    // First element of priority queue
    auto it = q.top();
    q.pop();
    // If the frequency of element is
    // less than desired frequency
    // then not possible
    if (it.first < temp.size()) {
        cout << "No\n";
        exit(0);
    }
    // If possible then assign value
    // to the matrix
    for (auto c : temp) {
        grid
            = it.second;
    }
    // Decrease the frequency
    it.first -= temp.size();
    // Again push inside queue
    q.push(it);
}
// Function to check if palindromic
// matrix of dimension N*N can be
// formed or not
void checkPalindrome(int A[], int N)
{
    // Stores the frequency
    map<int, int> mp;
    // Stores in the order of frequency
    priority_queue<pair<int, int> > q;
    // To store the palindromic
    // matrix if exists
    vector<vector<int> >
    grid(N, vector<int>(N));
    for (int c = 0; c < N * N; c++) {
        mp[A]++;
    }
    // Number of rows
    // Assign in priority queue
    for (auto c : mp)
        q.push({ c.second, c.first });
    // Middle index
    int m = N / 2;
    // Stores the indexes to be filled
    vector<pair<int, int> > temp;
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < m; j++) {
            // Find the opposite indexes
            // which have same value
            int revI = N - i - 1;
            int revJ = N - j - 1;
            temp = { { i, j },
                     { revI, j },
                     { i, revJ },
                     { revI, revJ } };
            // Check if all the indexes
            // in temp can be filled
            // with same value
            fill(temp, q, grid);
            temp.clear();
        }
    }
    // If N is odd then to fill the
    // middle row and middle column
    if (N & 1) {
        for (int i = 0; i < m; i++) {
            // Fill the temp
            temp = { { i, m },
                     { N - i - 1, m } };
            // Fill grid with temp
            fill(temp, q, grid);
            // Clear temp
            temp.clear();
            // Fill the temp
            temp = { { m, i },
                     { m, N - i - 1 } };
            // Fill grid with temp
            fill(temp, q, grid);
            temp.clear();
        }
        // For the middle element
        // of middle row and column
        temp = { { m, m } };
        fill(temp, q, grid);
    }
    cout << "Yes" << endl;
    // Print the matrix
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            cout << grid[i][j] << " ";
        }
        cout << endl;
    }
}
// Driver Code
int main()
{
    // Given array A[]
    int A[] = { 1, 1, 1, 1, 2, 3, 3, 4, 4 };
    int N = sizeof(A) / sizeof(A[0]);
    N = sqrt(N);
    // Function call
    checkPalindrome(A, N);
    return 0;
}


Yes
1 4 1
3 2 3
1 4 1