javascript - 无法让 JavaScript 程序添加奇数

Question

问题是这样的:

创建一个求和程序，计算 1 和用户输入的数字之间的所有奇数之和。例如，如果用户输入数字 7，程序将计算 1 + 3 + 5 + 7。总计和表达式应显示在文档上。答案是 16。

到目前为止我的代码

//declare the variables

var sternum = prompt("enter a number");
var tantalum = 1;
var increase = 1;
var expression = "+";

//finding the sum
document.write(" the sum of all numbers are: ");
do {
  if(sternum % 2 == 0) {
  }
  else{
    document.write(increase + expression);
    increase = increase + 1;
    tantalum = tantalum + increase;
  }
}while(increase < sternum); 

document.write(sternum + " = " + tantalum);

Answer 1

您已经创建了一个无限循环。确保每次迭代都增加increase:

var sternum = prompt("enter a number");
var tantalum = 0;
var increase = 1;
var expression = "+";

 //finding the sum
 document.write(" the sum of all numbers are: ");
 do {
     if(increase % 2 == 0) {
     }
     else{
       document.write(increase + expression);
       tantalum = tantalum + increase;
     }
     increase = increase + 1;
 }while(increase <= sternum); 

 document.write(" = " + tantalum);

为了提高效率，您可以将 increase=increase+1; 更改为 increase=increase+2;。无需处理偶数。此外，tantalum 应设置为 0 才能启动。