1 |
/* $Id$ */ |
/* $Id$ */ |
2 |
|
|
3 |
#include <stdio.h> |
#include <stdio.h> |
4 |
|
#include <stdlib.h> |
5 |
|
#include <limits.h> |
6 |
|
|
7 |
#define PRINTPRIME(x) if(is_prime(x)) printf("%i\n", x) |
#define BOOL int |
8 |
|
#define TRUE 1 |
9 |
|
#define FALSE 0 |
10 |
|
|
11 |
|
#define PRINTPRIME(x) if (is_prime(x)) printf("%i\n", x) |
12 |
#define PRINTERROR(message) fprintf(stderr, "ERROR: %s\n", message) |
#define PRINTERROR(message) fprintf(stderr, "ERROR: %s\n", message) |
13 |
|
|
14 |
/* check for prime number */ |
/* check for prime number */ |
15 |
int is_prime(int number) |
BOOL is_prime(long int number) |
16 |
{ |
{ |
17 |
int i; |
int i; |
18 |
for (i=2; i*i <= number; i++) { |
for (i=2; i*i <= number; i++) { |
19 |
if ((number % i) == 0) |
if ((number % i) == 0) |
20 |
return 0; |
return FALSE; |
21 |
|
} |
22 |
|
return TRUE; |
23 |
|
} |
24 |
|
|
25 |
|
/* convert from string to long, with error checking */ |
26 |
|
long int convert_number(const char *nptr) { |
27 |
|
long int number = strtol(nptr, (char **)NULL, 10); |
28 |
|
if (number == LONG_MAX) { |
29 |
|
PRINTERROR("Number '%s' is not in range of 'long int'."); |
30 |
} |
} |
|
return 1; |
|
31 |
} |
} |
32 |
|
|
33 |
int main(int argc, char * argv[]) |
int main(int argc, char * argv[]) |
34 |
{ |
{ |
35 |
|
|
36 |
if (argc == 1) { |
if (argc == 1) { |
37 |
PRINTERROR("No arguments given, will segfault under cygwin. :-)"); |
PRINTERROR("No arguments given."); |
38 |
return -1; |
return -1; |
39 |
} |
} |
40 |
|
|
54 |
|
|
55 |
/* (1) test-single-number mode: first argument is not a filename */ |
/* (1) test-single-number mode: first argument is not a filename */ |
56 |
if (fp == NULL) { |
if (fp == NULL) { |
57 |
PRINTPRIME(atoi(argv[1])); |
/* PRINTPRIME(atoi(argv[1])); */ |
58 |
|
PRINTPRIME(convert_number(argv[1])); |
59 |
|
|
60 |
/* (2) file mode: read numbers from file */ |
/* (2) file mode: read numbers from file */ |
61 |
} else { |
} else { |