function AandB(a, b) {
    let firstLetter = "0";
    let secondLetter = "1";
    let buf;
    for (let i = 0; i < a; i++) {
        buf = firstLetter
        for (let j = 0; j < b; j++) {
            if (j%2) {
                process.stdout.write(secondLetter);
            } else {
                process.stdout.write(buf);
            }
        }
        firstLetter = secondLetter;
        secondLetter = buf;
        process.stdout.write('\n');
    }
}

AandB (10, 10);