Program the prints prime numbers

I need to make a program that prints all prime numbers between 3 and 100.
Here is my code so far. Right now it only outputs the number 3. What is wrong with it? Thanks for any help.

Code:

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#include<iostream>
using namespace std;

int main()
{int num=3, checknum, remainder, answer=1;
        do{checknum=2;
                while(checknum<num-1)
                {remainder=num%checknum;
                if(remainder==0)
                {answer=0;
                continue;}
                else
                answer=1;
                checknum++;
                }
                if(answer=1)
                {cout<<""<<num;}
                num++;
        }while(num<101);
        return 0;
}

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Please!...My eyes hurt!...Indent your code!! Put code tags around it!

Hurry, I think I won't survive it...

Im sorry lol, I just copied and pasted it here, and it came out like that. I've never posted here before and I'm pretty new to programing

Quote:

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Originally Posted by cloudstrife910

Im sorry lol, I just copied and pasted it here, and it came out like that. I've never posted here before and I'm pretty new to programing

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Well then, edit your first post and try to do your best, please. Indent how you like, but code tags are mandatory (haven't you read the forum post that talks about that? You know, the one with that title??)

Quote:

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Originally Posted by cloudstrife910

here I'll try and rewrite it

Code:

---

#include<iostream>
using namespace std;

int main()
{int num=3, checknum, remainder, answer=1;
        do{checknum=2;
                while(checknum<num-1)
                {remainder=num%checknum;
                if(remainder==0)
                {answer=0;
                continue;}
                else
                answer=1;
                checknum++;
                }
                if(answer=1)
                {cout<<""<<num;}
                num++;
        }while(num<101);
        return 0;
}

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now will you help? pleassse?

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Meh, here's how I would do it:

Code:

---

#include<iostream>
using namespace std;

int main() {
        int num=3, checknum, remainder, answer=1;
        do {
                checknum=2;
               while(checknum<num-1) ;
                {
                        remainder=num%checknum;
                        if(remainder==0) {
                                answer=0;
                                continue;
                        } else
                                answer=1;
       
                        checknum++;
                }
                if(answer=1) {
                        cout<<""<<num;
                }
                        num++;
        } while(num<101);

        return 0;
}

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Now, while I was indenting, I realized that your code is a total mess. I am quite sure that it does not do anything you want at all. Can you try and explain what you wanted to do with each line or set of lines in it?

Hint: You have a while loop that does nothing, since it has an extra comma in front of it. It's highlighted.

There are two issues.

First, replace the "continue" with "break"; second, replace "if(answer=1)" with "if (answer == 1)".

Then it works perfect.

Edit: Helpful info! By using "continue", you are forcing it to stay in the loop when it first enters, so the program becomes a dud before anything happens. The "break" command is used to exit loops. And the unary equals was just a typo.

Code:

---

#include<iostream>
using namespace std;

int main() {
        int num=3, checknum, remainder, answer=1;
        do {
                checknum=2;
        while(checknum<num-1) //check if the number is between 3 and 100
        {
                remainder=num%checknum; //this will tell me if check num will divide evenly into it
                if(remainder==0) { //here if it does then I want the while loop to end and make answer=0;
                        answer=0;
                        continue;
                } else
                        answer=1;

                checknum++;
        }
        if(answer=1) {
                cout<<""<<num; //here if answer still equals 1 at the end of the loop I want it to print the number because the means it is prime
        }
                num++;
        } while(num<101);

        return 0;
}

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also that extra comma wasn't in my original code

You could use Sieve of Eratosthenes, and actually, at least one of the other language versions of this very wiki site has a working C++ code as example. ;)