TheAlgorithms-C/project_euler/problem_9/sol2.c
2020-06-05 12:20:25 -04:00

42 lines
1011 B
C

/**
* \file
* \brief [Problem 9](https://projecteuler.net/problem=9) solution
*
Problem Statement:
A Pythagorean triplet is a set of three natural numbers, \f$a < b < c\f$,
for which, \f$a^2 + b^2 = c^2\f$. For example, \f$3^2 + 4^2 = 9 + 16 = 25 =
5^2\f$. There exists exactly one Pythagorean triplet for which \f$a + b + c =
1000\f$. Find the product abc.
Given \f$a^2 + b^2 = c^2\f$ and \f$a+b+c = n\f$, we can write:
\f{eqnarray*}{
b &=& \frac{n^2 - 2an}{2n - 2a}\\
c &=& n - a - b
\f}
*/
#include <stdio.h>
#include <stdlib.h>
/** Main function */
int main(void)
{
int N = 1000;
for (int a = 1; a < 300; a++)
{
long tmp1 = N * N - 2 * a * N;
long tmp2 = 2 * (N - a);
div_t tmp3 = div(tmp1, tmp2);
int b = tmp3.quot;
int c = N - a - b;
if (a * a + b * b == c * c)
{
printf("%d x %d x %d = %ld\n", a, b, c, (long int)a * b * c);
return 0;
}
}
return 0;
}