<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title></title>
    <script type="text/javascript">
      //计算100以内所有奇数的和
      window.onload = function(){
        var h = document.getElementById('h');
        var hh = document.getElementById('hh');
        var sum = 0;
        for(var i = 1; i < 100; i++){ //第一中方法
          if(i % 2 == 0){
            // console.log(i);
            continue;
          }
          // console.log(i);
          sum += i;
        }
        // alert(sum);
        h.innerHTML = '100以内所有奇数和为:' + [sum];
        var sum2 = 0;
        for(var j = 1; j <= 100; j=j+2){
          //console.log(j);
          sum2 += j;
        }
        hh.innerHTML = '100以内所有奇数和为:' + [sum2];
      }
    </script>
  </head>
  <body>
    <h2 id="h"></h2>
    <h2 id="hh"></h2>
  </body>
</html>

js计算100以内所有奇数的和_i++