poker.html

<script>
    let poker = [];
    for (let i=0; i<6; i++){
        let rand = parseInt(Math.random()*6);  // 0 - 51
        // 檢查是否重複
        // 檢查機制
        let isRepeat = false;
        for (let j=0; j<i; j++){
            if (poker[j] == rand){
                // 重複了
                isRepeat = true;
                break;
            }
        }

        if (isRepeat){
            i--;
            continue;
        }
        poker[i] = rand;
    }

    for (let i in poker){
        document.write(poker[i] + "<br>");
    }

</script>