for/js_0601practice05_for_loop.html

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<head>
    <meta charset="UTF-8">
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    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
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<body>
    <script>
        //0601_巢狀迴圈
        //兩層迴圈

        //畫星星 
        //input = 5 時
        //1*****
        //2****
        //3***
        //4**
        //5*

        //第一層input 5 =>5層
        //步驟一
        
        input = 5;
        for(let i =0; i < 5; i++){
            document.write(i);

            for(let j = 0; i >=j; j++){
                document.write(j);
            }


            document.write("<br>");
        }


        //步驟二

        input = 5;
        tmp = input;
        for(let i =0; i < input; i++){
            console.log('old tmp =>' + tmp);
            tmp--; //tmp = tmp -1;
            console.log('mew tmp =>' + tmp);
            document.write(i);

            for(let j =0; j <= tmp ; j++){
                //document.write(j);
                document.write('*');

        }
            document.write("<br>");
        }


        //for loop 星星練習3
        //input = 5
        //*****
        //*****
        //*****
        //*****
        //*****

        //方法一

        /*let input = 5;
        for(let i = 0 ; i < input ; i++){
            console.log(i + "*****");
            document.write(i)
        }*/


        //方法二 *30
        let input =5;
        let inputJ = 30;
        for(let i = 0 ; i < input ; i++){
            // 1.蓋大樓
            // document.write(i);
            // 2.畫input數量的星星
            for(let j = 0 ; j < inputJ ; j++){
                // document.write(j);
                document.write('*');
            }
            document.write('<br>');

        }

        //練習題
        //for loop 星星練習
        //input = 5 
        //  * 
        // ***
        //*****
        //******
        //********

        sum = '';
        input = 5;
        for(let i = 0 ; i < input ; i++){
            // sum = sum + '*';
            sum += '*';
            // console.log(`${i+1} => ${sum}`);
            document.write(`${i+11} => ${sum} <br>`)
            // document.write(`${i} => ${sum} <br>`)
            // document.write(`${sum} <br>`)
        }


    </script>
</body>
</html>