NEWBIE

[Guest_imported]

NEWBIE IN C++ I NEED HELP WITH CODING DIVISIBILITY BY CODE SHOULD PRINT OUT "PRIME" IF NOT DIVISIBLE AND IF IT IS DIVISIBLE NEED TO PRINT OUT NUMBER AND COMMAS AFTER EACH NUMBER .TY IN ADVANCE

OUTOUT

2 PRIME
3 PRIME
4 2
5 PRIME
.
.
.
100 2,4,10,20,25,50

 

[Guest_imported]

Try an If Statement !!!

 

[Zyrenthian]

write a function to factor a number and return a list of factors MAYBE a CArray, CList??? If all that was returned was 1 and the number it is prime. Also realize there are many mathamatical ways to determine if a number is divisible by 2 (easy) , 3 (all the numbers in the number added together is a number divisible by 3 etc...


Matt

 

[vkarthik]

let n be that no.

int flag=0;
for(int i=2;i<=n/2;i++)
{
if(n%i==0)
{
flag=1;
cout << i << &quot;,&quot;;
}
}
if(flag==0)
{
cout << &quot;prime&quot;;
}

this should work nearly the way u want.

luv
Karthik.

 

[Jeffray]

this recursive function will work faster:
at last you'll get a prime number list in array y.
#include <math.h>
void prime(int *y, int &n)
{
if (y[n]%2 == 0) {
y[n+1] = y[n] / 2;
y[n] = 2;
n++;
prime(y,n);
return;
}else{
int i = 3;
int M = sqrt((double)y[n]);
while (i <= M +1){
if (y[n] %i == 0) {
y[n+1] = y[n] / i;
y[n] = i;
n++;
prime(y,n);
return;
}
i +=2;
}
}
}
void main(){
int y[50];
y[0] = 100;
int n = 0;
prime(y,n);
}