void main()
{
int i,j,n;
long max;
clrscr();
puts("============================================================");
puts("|| This program will verify the Goldbach Guess. ||");
puts("|| That is any positive even number can be broken up into ||");
puts("|| the sum of two prime numbers. ||");
puts("|| e.g., 4=2+2, 6=3+3, 8=3+5, 10=3+7, 12=5+7,... ||");
puts("============================================================");
printf("\n >> Please input the scale n you want to verify : ");
scanf("%ld",&max);
printf("\n >> Now the program starts to verify the even number\n");
printf(" >> less than %ld equals to sum of two prime numbers.\n\n",max);
for(i=4,j=0;i<=max;i+=2)
{
for(n=2;n<i;n++) /*将偶数i分解为两个整数*/
if(fflag(n)) /*分别判断两个整数是否均为素数*/
if(fflag(i-n))
{
printf("%4d=%2d+%2d ",i,n,i-n); /*若均是素数则输出*/
j++;
if(j==5)
{
printf("\n");
j=0;
}
break;
}
if(n==i) printf("error %d\n",i);
}
puts("\n >> Press any key to quit...");
getch();
}
STATIC void
expandmeta(shinstance *psh, struct strlist *str, int flag)
{
char *p;
struct strlist **savelastp;
struct strlist *sp;
char c;
/* TODO - EXP_REDIR */
while (str) {
if (fflag(psh))
goto nometa;
p = str->text;
for (;;) { /* fast check for meta chars */
if ((c = *p++) == '\0')
goto nometa;
if (c == '*' || c == '?' || c == '[' || c == '!')
break;
}
savelastp = psh->exparg.lastp;
INTOFF;
if (psh->expdir == NULL) {
size_t i = strlen(str->text);
psh->expdir = ckmalloc(psh, i < 2048 ? 2048 : i); /* XXX */
}
expmeta(psh, psh->expdir, str->text);
ckfree(psh, psh->expdir);
psh->expdir = NULL;
INTON;
if (psh->exparg.lastp == savelastp) {
/*
* no matches
*/
nometa:
*psh->exparg.lastp = str;
rmescapes(psh, str->text);
psh->exparg.lastp = &str->next;
} else {
*psh->exparg.lastp = NULL;
*savelastp = sp = expsort(*savelastp);
while (sp->next != NULL)
sp = sp->next;
psh->exparg.lastp = &sp->next;
}
str = str->next;
}
}
