#include<iostream>

#include<cstdio>

#include<cstdlib>

#include<cstring>

#include<climits>

using namespace std;

typedef long long LL;

int n, m;

char a[][];

bool flg[];

inline char getans(int x, int y) {

    char ret = a[x][y];

    if (!ret) {

        ret = 'A';

        while (ret == a[x - ][y] || ret == a[x + ][y] || ret == a[x][y - ] || ret == a[x][y + ]) ++ ret;

    }

    return ret;

}

inline void cover(int x, int y) {

    char c = getans(x, y);

    putchar(c);

    if (a[x][y]) return;

    int sz = ;

    while(x + sz <= n && y + sz <= m && getans(x, y + sz) == c) {

        sz ++;

    }

    sz --;

    for (int i = x; i <= x + sz; ++ i)

        for (int j = y; j <= y + sz; ++ j)

            a[i][j] = c;

}

int main() {

    scanf("%d%d", &n, &m);

    for (int i = ; i <= n; ++ i) {

        for (int j = ; j <= m; ++ j)

            cover(i, j);

        putchar('\n');

    }

}