ProjectEuler/c/0006.c

#include <stdio.h>
#include <stdint.h>

int
main(int argc, const char **argv)
{
	uint64_t res = 0;
	uint64_t i = 1;
	uint64_t sumsqr = 0;
	uint64_t sum = 0;
	uint64_t upper_limit = 100;

	for ( i = 1; i <= upper_limit; ++i ) {
		sumsqr += i * i;
		sum += i;
	}
	res = (sum * sum) - sumsqr;

	printf("Result = %ld!\n", res);
	(void) argc; (void) argv;
	return 0;
}