printing prime numbers error
i'm trying to print prime numbers between 1 and 100 but all that comes out is 2 and a very large negative number. can you guys please point out any errors in my code?
#include<stdio.h>
#include<math.h>
int main(void)
{
int n, x;
do
{
printf("2 \n");
printf("%d \n", prime(n));
}
while (prime(n)==x);
return 0;
}
int prime(int n, int m, int x)
{
for (n=3; n<=100; n+=2)
{
for (m=2; m<<n; m++)
{
if (n%m==0)
return 0;
else
return x;
}
}
}
#include<stdio.h>
#include<math.h>
int main(void)
{
int n, x;
do
{
printf("2 \n");
printf("%d \n", prime(n));
}
while (prime(n)==x);
return 0;
}
int prime(int n, int m, int x)
{
for (n=3; n<=100; n+=2)
{
for (m=2; m<<n; m++)
{
if (n%m==0)
return 0;
else
return x;
}
}
}
and how this compiles is beyond me (must be k&r C) since prime() is not declared before
it is called and it isn't even called with the correct number of parameters.
it is called and it isn't even called with the correct number of parameters.
| neither x nor n is initialized in main() before you use them... |
by that you mean setting initial values?
so
#include<stdio.h>
#include<math.h>
int main(void)
{
int n=1;
char x;
do
{
printf("2 \n");
printf("%d \n", prime(n));
}
while (prime(n)=='x');
return 0;
}
int prime()
{
int n=1;
int m=1;
char x;
for (n=3; n<=100; n+=2)
{
for (m=2; m<n; m++)
{
if (n%m!=0)
return x;
}
}
}
i got rid of the negative value by doing that, thanks!
but now i get 2 and 8...
| m<<n is a bitshift by n positions; you meant . |
i changed it to m<n instead, to mean that m goes until 1 less than n. is that right?
| since prime() is not declared before it is called and it isn't even called with the correct number of parameters |
i removed them (n, m, and x) from prime() and declared them later on. i think that helped, thanks!
Last edited on
Topic archived. No new replies allowed.