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#include <stdlib.h>
#include <stdio.h>
int gen(int p, int pmax, int q)
{
int a, b, c;
for (; p < pmax; p += 2)
{
int _q = q;
for (; _q < p; _q += 2)
{
if (!pythagorean_triplet(p, _q, &a, &b, &c))
continue;
printf("p:%d q:%d a:%d\tb:%d\tc:%d\n", p, _q, a, b, c);
if (a+b+c == 1000)
goto found;
if (1000 % (a+b+c) == 0)
{
int m = 1000 / (a+b+c);
printf("triplet sum (%d) is divisor of 1000, multiply by %d\n",
a+b+c, m);
a *= m;
b *= m;
c *= m;
if (a+b+c == 1000)
goto found;
}
}
}
return 0;
found:
printf("got it: a:%d b:%d c:%d a*b*c=%d\n", a, b, c, a*b*c);
return 1;
}
int main(int argc, char **argv)
{
// some different ways to generate pythagorean triples, let's hope one of
// these yields the result
if (gen(3, 20, 3))
return 0;
printf("--\n");
if (gen(3, 20, 2))
return 0;
printf("--\n");
if (gen(2, 20, 3))
return 0;
// and of course the brute-force way :-) (this could be optimized by
// making the condition b<1000 -> b<1000-a and just stating c=1000-a-b
// instead of iterating values of c).
// int a, b, c;
// for (a = 1; a < 1000; a++)
// {
// for (b = a+1; b < 1000; b++)
// {
// for (c = b+1; c < 1000; c++)
// {
// if ((a + b + c == 1000) && (a*a + b*b == c*c))
// {
// printf("a:%d b:%d c:%d a*b*c:%d\n", a, b, c, a*b*c);
// return 0;
// }
// }
// }
// }
return 0;
}
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