#include <bits/stdc++.h>
using namespace std;

using i8 = int8_t;
using i16 = int16_t;
using i32 = int32_t;
using i64 = int64_t;
using isize = ptrdiff_t;
using u8 = uint8_t;
using u16 = uint16_t;
using u32 = uint32_t;
using u64 = uint64_t;
using usize = size_t;
using f32 = float_t;
using f64 = double_t;

inline constexpr i32 Modulus = 1e9 + 7;

int main(void)
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    u16 n, m;
    cin >> n >> m;

    auto grid = vector<string>(n);
    for (auto& row : grid)
    {
        cin >> row;
    }

    for (u16 y = 0; y < n; y += 1)
    {
        for (u16 x = 0; x < m; x += 1)
        {
            char& color = grid[y][x];
            u16 parity = (y + x) & 0b1;

            char targetColor = 'A' + parity;
            targetColor += (targetColor == color) << 1;

            color = targetColor;
        }
    }

    for (auto& row : grid)
    {
        cout << row << '\n';
    }

    return 0;
}