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#include <stdio.h>
/*
* much faster than python version, though less optimized...
*
* to filter out duplicates and add numbers:
* $ ./032 | sort -u | tr "\n" "+" | sed 's/+$/\n/' | bc
*
*/
int is_pandigital(long int a, long int b, long int c)
{
char digits[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
char digit;
int i;
while(a > 0)
{
digit = a % 10;
if(digit == 0 || digits[digit]++)
return 0;
a /= 10;
}
while(b > 0)
{
digit = b % 10;
if(digit == 0 || digits[digit]++)
return 0;
b /= 10;
}
while(c > 0)
{
digit = c % 10;
if(digit == 0 || digits[digit]++)
return 0;
c /= 10;
}
for(i=1; i<10; i++)
if(digits[i] != 1)
return 0;
return 1;
}
int main(void)
{
long int limit = 10000;
long int a, b, c;
for(a=2; a<limit; a++)
{
for(b=2; b<limit; b++)
{
c = a * b;
if(c > limit)
break;
if(is_pandigital(a, b, c))
printf("%ld\n", c);
}
}
return 0;
}
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