Manchester-列出最简真分数序列*

int greast(int m, int n)
{
	int a = 0;
	while (m % n)
	{
		a = m % n;
		m = n;
		n = a;
	}
	return n;
}

int main()
{
	int i = 0;
	int arr[50] = { 0 };
	for (i = 0; i < 39; i++)
	{
		arr[i] = greast(40, i + 1);
		if (arr[i] == 1)
		{
			printf("%d/40,", i + 1);
		}
	}
	printf("\n");
	return 0;
}

#include"stdio.h"
#include"math.h"
#include"string.h"
int main()
{   printf("%d/40\n",1);
for(int i=2,a;i<40;i++)
{
    if((40%i)!=0&&(i%2)!=0&&(i%5)!=0)
    printf("%d/40\n",i); 
}

}

先求质因数才是最好的

#include <stdio.h>

int main(void)
{
	int num = 40;
	int i = 0, x = 0, y = 0, quo = 0, rem = 0;
	for (i = 1; i <= 40; i += 2) {
		x = num;
		y = i;
		quo = rem = 0;
		while (1) {
			quo = x/y;
			rem = x%y;
			if (0 == rem)break;
			x = y;
			y = rem;
		}
		if (1 == y) {
			printf("%d/40,", i);
		}
	}
	return 0;
}
要是很大的数，修改num值就可以了

老哥，要是是一个很大的数呢?