Prime numbers using functions. Writing 1-100 prime numbers to a file? Need help with programming assignment

Answer 1

woah man I'm not looking for someone to do my homework....im frustrated because I can't figure it out.

Answer 2

I was trying to do it for 8 hours yesterday.

Answer 3

And again, you didn't ask a question, or specified the language
Post the lines of code you made in 8 hours yesterday

Answer 4

#include<iostream>
using namespace std;
bool isPrime(int, int);
int main() {
int number;
int number2 = 1;
cout << "Please enter a number between 1 and 100.\n\n";
cin >> number;
isPrime(number, number2);
if (isPrime(number, number2)==true) {
cout << number << " is a prime number.";
}
else cout << number << " The number is not a prime number.";
system("pause");
}
bool isPrime(int number, int number2){
bool status;
if (number % number2 == 0) {
status = true;
}
else if (number % number2 > 0) {
status = false;
}
return status;
}

Answer 5

Like I said I'm not trying to get someone to do my homework..im at a frustrated level and my school doesn't offer any help...

Answer 6

and I'm trying to learn coding. I'm not trying to get someone to do it for me

Answer 7

Your program ask for a number from 1-100 and then you check if it is prime
And I think it is wrong
I think they are requesting you a program that prints ALL the prime numbers from 1 to 100
And you are printing in terminal, and you need to print the numbers in a file

Answer 8

A prime number is a number that is only evenly divisible by itself and 1. For example, the number 5 is prime because it can only be evenly divided by 1 and 5. The number 6, however, is not prime because it can be divided evenly by 1, 2, 3, and 6.
Write a function name isPrime , which takes an integer as an argument and returns true if the argument is a prime number, or false otherwise. Use the isPrime function in a program that stores a list of all the prime numbers from 1 through 100 in a file named allprimes.dat.
TIP: Recall that the % operator divides one number by another, and returns the remainder of the division. In an expression such as num1 % num2 , the % operator will return 0 if num1 is evenly divisible by num2 .

Answer 9

with mine its returning every number the user types in as true for a prime number..

Answer 10

That's because you declared variable number2 is equal to 1
And any number divided by 1, gives you a reminder of 0
You only need one parameter in your function isPrime

Answer 11

oh duh....but if I put number%1 !=0 it gives me an error

Answer 12

why would u use a decrement instead of an increment?

Answer 13

#include<iostream>
using namespace std;
bool isPrime(int, int);
int main() {
int number;
int number2 = 1;
cout << "Please enter a number between 1 and 100.\n\n";
cin >> number;
isPrime(number, number2);
if (isPrime(number, number2)==true) {
cout << number << " is a prime number.";
}
else cout << number << " The number is not a prime number.";
system("pause");
}
bool isPrime(int number, int number2) {
bool status;
//this is what I changed. why wouldn't it work?
for (number = number2; number2 = number2++;) {
}
if (number % number2 == 0) {
status = true;
}
else if (number % number2 != 0) {
status = false;
}
return status;
}

Answer 14

#include<iostream>
using namespace std;
bool isPrime(int, int);
int main() {
int number;
int number2 = 1;
cout << "Please enter a number between 1 and 100.\n\n";
cin >> number;
isPrime(number, number2);
if (isPrime(number, number2)==true) {
cout << number << " is a prime number.";
}
else cout << number << " The number is not a prime number.";
system("pause");
}
bool isPrime(int number, int number2) {
bool status;
for (number = number2; number2 = number2++;) {
if (number % number2 == 0) {
status = true;
}
else if (number % number2 != 0) {
status = false;
}
}
return status;
}
// I mean all of this...it stops after you input the number

Answer 15

That's because your function is declared in the top with one parameter, but after you request the number, that function is expecting 2 parameters
You have to modify your function,
isPrime(number)
The for loop and if needs to be equal to ones I posted

Answer 16

it has two parameters in the function, both are int

Answer 17

Only one is needed
And you are only asking for one to user

Answer 18

#include<iostream>
using namespace std;
bool isPrime(int);
int main() {
int number;
cout << "Please enter a number between 1 and 100.\n\n";
cin >> number;
isPrime(number);
if (isPrime(number)==true) {
cout << number << " is a prime number.\n\n";
}
else cout << number << " The number is not a prime number.\n\n";
while (number > 0) {
cout << "Please enter a number between 1 and 100.\n\n";
cin >> number;
isPrime(number);
if (isPrime(number) == true) {
cout << number << " is a prime number.\n\n";
}
else cout << number << "is not a prime number.\n\n";
}
system("pause");
}

Answer 19

its still not working properly.. I put in a while loop

Answer 20

All wrong