Как найти сумму четных чисел до 1000

asked Jul 14, 2016 at 3:04

Your for loop is incorrect.
You have

for(var x=2; x!=1000; x+2)

Where you should do

for(var x=2; x<=1000; x = x+2)

Currently, your loop never updates x so it has the same value all the time. Statement 3 in the for loop is executed as it is so your code just executes x+2 which is just some number. The code I suggested above updates x to be equal to x+2.

Your condition terminates the loop once x is equal to 1000 so 1000 is not added to the sum. You need to either break the loop when x is equal to 1002 or better use

x<=1000

Putting a semi-colon after the if condition means that you want to do nothing if that condition is satisfied. If you don’t put a “{” after the if then only one statement following the if statement is executed when your condition is satisfied. When you put a semi-colon, then you execute an empty statement.

answered Jul 14, 2016 at 3:07

Really, there’s no reason you actually have to run the loop, since this function always returns the same number.

function get_the_sum()
{
    //Sum of even numbers <= 1000
    //=(1000+0 + 998+2 + 996+4 ... + 0+1000) / 2
    return 500*501;
}

answered Jul 14, 2016 at 3:21

WesleyACWesleyAC

5246 silver badges11 bronze badges

You have to make sure you increment the loop properly. Other than that, your reasoning seems perfectly right.
You are doing:

for(x=0;x!=1000;x+2)

whereas you should be doing something like:

for(x=0;x<=1000;x+=2) 

Here, a += b is a shortcut for a = a + b. Also, <=1000 includes 1000 in the sum as well.

As for your second question, a semicolon after an if statement invalidates an if statement as if no {} are placed after an if statement, it only executes the condition on the statements till it encounters its first semicolon.
If you have more than 1 line of code to execute in if statement you may implement it like this:

if(condition) {
    code line 1;
    code line 2;
    code line 3;
}

answered Jul 14, 2016 at 3:07

67 &&-%%68’®[{=¢£©™[{=

Определим объем одного слова. Слово можно представить как
abbbbbc
где a принимает одну из восьми букв, а c – одну из четырёх. Буквы b принимают одно из 32 значений.
Получается, что у нас:
a – объем 3 бит, т.к. 2^3 = 8
b – объем 5 бит, т.к. 2^5 = 32
c – объем 2 бит, т.к. 2^2 = 4
То есть объем всего слова равен 3+5*5+2 = 30 бит.

Всего 10 слов, без учета пробелов объем фразы будет равен 30*10 = 300 бит.

G$5*$A12 , знак $ необходим для закрепления ячейки в формуле , в
<span>D$5 закрепляется строка , а столбец , при переносе формулы изменяется
ну и аналогично с </span><span>$A10.</span><span><span>Столбец</span> закрепляется , а строка изменяется .  </span> 

F:/DOCUM/LENA/letter.doc
F:/DOCUM/LENA/Tables.xls
F:/DOCUM/IVAN/my.doc

F:/ARCHIV/MAIN/letter.doc
F:/ARCHIV/MAIN/my.doc
F:/ARCHIV/1.zip