SGU 119

欧几里得- -要分N种情况- -

#include<cstdio>
#include<algorithm>
using namespace std;
int gcd(int x,int y){if (y==0) return x;return gcd(y,x%y);}
struct node
{
    int x,y;
        friend bool operator < (const node &a, const node &b)
        {
            if(a.x != b.x) return a.x < b.x;
            return a.y < b.y;
        }
}ans[10030];
int main()
{
    int n,a1,b1;
    scanf("%d%d%d",&n,&a1,&b1);
    a1=a1%n;b1=b1%n;
    int i=n/gcd(n,a1),j=n/gcd(n,b1);
    int sum=i*j/gcd(i,j);
    for (int i=1;i<=sum;i++) 
    {
        ans[i].x=(a1*i)%n;
        ans[i].y=(b1*i)%n;
    }
    sort(ans+1,ans+1+sum);
    printf("%d\n",sum);
    for (int i=1;i<=sum;i++) printf("%d %d\n",ans[i].x,ans[i].y);
    return 0;
}