ебитесь конем такие задачи

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

using namespace std;



int* Get_Line(int** a, int k, int n) {
    int SIZE, i, j, ptr = 0;
    if (k < n) {
        SIZE = k + 1;
        i = k;
        j = 0;
    }
    else {
        SIZE = 2 * n - 1 - k;
        i = n - 1;
        j = k - n + 1;
    }
    int* res = new int[SIZE];


    while (i >= 0 && j < n)
        res[ptr++] = a[i--][j++];

    return res;
}

int** init(int n)
{
    int** a = new int*[n];
    for(int i = 0; i < n; ++i)
        a[i] = new int[n];
    for (int i = 0; i < n; ++i)
        for (int j = 0; j < n; ++j)
        cin >> a[i][j];
    return a;
}


void sort(int* a, int n)
{
    for (int i = 0; i < n; ++i)
    {
        int min = a[i];
        int idx = i;
        for (int j = i; j < n; ++j)
            if (a[j] < min)
            {
                min = a[j];
                idx = j;
            }
        swap(a[i], a[idx]);
    }
}

void Replace(int** a, const int* arr, int k, int n) {
    int i, j, ptr = 0;
    if (k < n) {
        i = k;
        j = 0;
    }
    else {
        i = n - 1;
        j = k - n + 1;
    }
    while (i >= 0 && j < n)
        a[i--][j++] = arr[ptr++];
}

int main()
{
    int n;
    cin >> n;
    int** a = init(n);

    for (int k = 0; k < 2*n - 1; ++k)
    {
        int* temp = Get_Line(a, k, n);
        int SIZE;
        if (k < n)
            SIZE = k + 1;
        else
            SIZE = 2 * n - k - 1;
        sort(temp, SIZE);
        Replace(a, temp, k, n);
    }


    cout << endl;
    for (int i = 0; i < n; ++i)
    {
        for (int j = 0; j < n; ++j)
            cout << a[i][j] << ' ';
        cout << '\n';
    }
    system("pause");
}