2019-09-22 10:33:18 +02:00

64 lines
1.1 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "projecteuler.h"
int main(int argc, char **argv)
{
int i, j, tmp;
long int n, max = 0;
double elapsed;
struct timespec start, end;
clock_gettime(CLOCK_MONOTONIC, &start);
for(i = 1; i < 10000; i++)
{
n = 0;
j = 1;
do
{
tmp = i * j;
n += tmp;
j++;
if(n > max && is_pandigital(n, 9))
{
max = n;
}
if(i * j < 10)
{
n *= 10;
}
else if(i * j < 100)
{
n *= 100;
}
else if(i * j < 1000)
{
n *= 1000;
}
else if(i * j < 10000)
{
n *= 10000;
}
else if(i * j < 100000)
{
n *= 100000;
}
}while(n <= 987654321);
}
clock_gettime(CLOCK_MONOTONIC, &end);
elapsed = (end.tv_sec - start.tv_sec) + (double)(end.tv_nsec - start.tv_nsec) / 1000000000;
printf("Project Euler, Problem 38\n");
printf("Answer: %ld\n", max);
printf("Elapsed time: %.9lf seconds\n", elapsed);
return 0;
}