TheAlgorithms-C/project_euler/problem_9/sol2.c
2020-05-29 16:13:52 -04:00

38 lines
859 B
C

#include <stdio.h>
#include <stdlib.h>
/**
Problem Statement:
A Pythagorean triplet is a set of three natural numbers, a < b < c, for which,
a^2 + b^2 = c^2
For example, 3^2 + 4^2 = 9 + 16 = 25 = 5^2.
There exists exactly one Pythagorean triplet for which a + b + c = 1000.
Find the product abc.
Given a^2 + b^2 = c^2 and a+b+c = n, we can write:
b = (n^2 - 2*a*n) / (2*n - 2*a)
c = n - a - b
**/
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;
}