addends of a number

[hisoka]

How to write a Javascript program that find the addends of a number ?

[justsomeguy]

Loop starting at 0 or 1 and ending at half the number.

[hisoka]

this is what I get so far :

 

for example if I want the addends of 40 then :

 

for( var i = 0 ; i<=20 ; i++)

{
console.log(tmp = +i);
}

 

and I get

0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20

all the numbers that when added to each other give 40

 

if I am wrong could you correct me ?

Edited February 24, 2016 by hisoka

[davej]

Good grief.

[hisoka]

now more difficult . I would like to write a program that gives me the different combinations by the number of addends which when add together gives a number . for example I put 25 as a number then the program generates to me the different combinations of addends like this

 

1+24 = 25

2+23=25 2 combinations of addends

5+20= 25

 

1+1+23=25

4+2+21=25 3 combinations of addends

7+3+15=25

 

7+9+6+3=25

4+10+5+6=25 4 combinations of addends

8+12+1+4=25

 

2+3+7+8+5=25 5 combinations of addends

9+5+4+6+1=25

 

5+6+4+3+2+1+4=25 6 combinations of addends

 

any hint on how to do it ?

[Ingolme]

This is more of a math problem than a programming one. Once you've figured out the mathematical solution, the programming one will be easy to implement.

 

Is it a requirement that none of the addends are identical?

[justsomeguy]

The solution for 2 is what I suggested with the loop, but you only printed 1 of them. It should be obvious how to find the second one. The others would use a series of nested loops.

[davej]

What does this mean?

 

console.log(tmp = +i);

 

[hisoka]

console.log(tmp = +i);

 

used to print all the numbers that the loop engenders

[hisoka]

"Is it a requirement that none of the addends are identical?"

 

the addends can be identical or not

 

for example addends of 10 can be 5+5 = 10 or 6+4=10

[justsomeguy]

console.log(tmp = +i);

 

used to print all the numbers that the loop engenders

I think the point of the question was why are you assigning it to the variable tmp, and why are you explicitly making it a positive integer when it should already be one? What's wrong with console.log(i)?

 

the addends can be identical or not

You're looking at a series of nested loops, then. The first step is to do the loop for 2 addends and then go from there.

[Ingolme]

Perhaps it's possible to do this for an unlimited number of addends using a recursive function, but I would have to do some homework to figure it out.

[davej]

"Is it a requirement that none of the addends are identical?"

 

the addends can be identical or not

 

for example addends of 10 can be 5+5 = 10 or 6+4=10

 

Okay, but then you have to consider...

1+1+1+1+1+1+1+1+1+1 = 10

...and really for any positive integer the addends would simply be the set of all smaller positive integers.

[justsomeguy]

It would make more sense to cap it at a certain number, like only up to 2, 3, 4 etc addends.