# Codeforces 1143 D. The Beatles（数学）

## Description

Recently a Golden Circle of Beetlovers was found in Byteland. It is a circle route going through $n⋅k$ cities. The cities are numerated from $1$ to $n⋅k$, the distance between the neighboring cities is exactly $1$ km.

Sergey does not like beetles, he loves burgers. Fortunately for him, there are n fast food restaurants on the circle, they are located in the $1$-st, the $(k+1)$-st, the $(2k+1)$-st, and so on, the $((n−1)k+1)$-st cities, i.e. the distance between the neighboring cities with fast food restaurants is $k$ km.

Sergey began his journey at some city $s$ and traveled along the circle, making stops at cities each $l$ km $(l>0)$, until he stopped in $s$ once again. Sergey then forgot numbers $s$ and $l$, but he remembers that the distance from the city $s$ to the nearest fast food restaurant was $a$ km, and the distance from the city he stopped at after traveling the first $l$ km from $s$ to the nearest fast food restaurant was $b$ km. Sergey always traveled in the same direction along the circle, but when he calculated distances to the restaurants, he considered both directions.

Now Sergey is interested in two integers. The first integer $x$ is the minimum number of stops (excluding the first) Sergey could have done before returning to $s$. The second integer $y$ is the maximum number of stops (excluding the first) Sergey could have done before returning to $s$.

## Input

The first line contains two integers $n$ and $k$ $(1≤n,k≤100000)$ — the number of fast food restaurants on the circle and the distance between the neighboring restaurants, respectively.

The second line contains two integers $a$ and $b$ $(0≤a,b≤\frac{k}{2})$ — the distances to the nearest fast food restaurants from the initial city and from the city Sergey made the first stop at, respectively.

## Output

Print the two integers $x$ and $y$.

## Examples input

2 3
1 1


## Examples output

1 6


## AC 代码

#include <bits/stdc++.h>
#define IO                       \
ios::sync_with_stdio(false); \
cin.tie(0);                  \
cout.tie(0);
#define mem(a, x) memset(a, x, sizeof(a))
#define per(x, a, b) for (int x = a; x <= b; x++)
#define rep(x, a, b) for (int x = a; x >= b; x--)

using namespace std;
typedef long long LL;
typedef pair<int, int> P;
const int maxn = 1e5 + 10;
const int mod = 1e9 + 7;
const double eps = 1e-8;

LL n, k, a, b;
vector<LL> l;

void getl(LL start) {
l.push_back(k + 1 + b - start);
l.push_back(2 * k + 1 - b - start);
}
void solve() {
l.clear();
if (k % 2 == 0 && k / 2 == a) {
getl(1 + a);
} else {
getl(1 + a);
getl(k + 1 - a);
}
int len = l.size();
for (int i = 0; i < len; i++) {
l[i] = (l[i] % k + k) % k;
}
LL minn = LLONG_MAX;
LL maxx = LLONG_MIN;
LL nk = 1LL * n * k;
for (auto s : l) {
for (int i = 0; i < n; i++) {
LL now = __gcd(s + 1LL * i * k, nk);
minn = min(minn, nk / now);
maxx = max(maxx, nk / now);
}
}
cout << minn << " " << maxx << endl;
}
int main() {
#ifdef LOCAL_IM0QIANQIAN
freopen("test.in", "r", stdin);
//    freopen("test.out", "w", stdout);
#else
IO;
#endif // LOCAL_IM0QIANQIAN

while (cin >> n >> k >> a >> b) {
solve();
}
return 0;
}


### 2 只已被捕捉

• 啊哈哈你好 Miui浏览器 | 13.8.12 Android 8.1.0

没了别人能拿你怎么样，你又不会死
~来自一个曾经非常渴望陪伴的后来被害的朋友

• 千千 Chrome | 88.0.4324.150 Windows 10

怎么回事？