// TASK 8
#include<bits/stdc++.h>
#define all(x) begin(x),end(x)

using namespace std;

using ll = long long;
using lll = __int128;
using ld = long double;
using pt = pair<int, int>;


int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    ll a, b, c, d;
    cin >> a >> b >> c >> d;
    // a / b <= sqrt(x)
    // a <= sqrt(x) * b
    // a * a <= x * b * b

    // sqrt(x) * d <= c
    // x * d * d <= c * c

    ll left = 0;
    ll right = 2e18;
    ll mid;
    ll left_ans = 2e18;
    while (left <= right) {
        mid = (left + right) >> 1;
        if (lll(a) * a <= lll(mid) * b * b) {
            left_ans = mid;
            right = mid - 1;
        } else {
            left = mid + 1;
        }
    }

    left = 0;
    right = 2e18;
    ll right_ans = -1;

    while (left <= right) {
        mid = (left + right) >> 1;
        if (lll(mid) * d * d <= lll(c) * c) {
            right_ans = mid;
            left = mid + 1;
        } else {
            right = mid - 1;
        }
    }

    ll answer = right_ans - left_ans + 1;
    if (answer < 0) answer = 0;
    cout << answer << '\n';
}

// TASK 9
#include<bits/stdc++.h>
#define all(x) begin(x),end(x)

using namespace std;

using ll = long long;
using lll = __int128;
using ld = long double;
using pt = pair<int, int>;


int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    ll x, y;
    ll a, b, c, d;
    cin >> x >> y;
    cin >> a >> b >> c >> d;

    ll answer = min({
        a - 0,
        x - c,
        b - 0,
        y - d
    });
    cout << answer << '\n';
}

// TASK 10
#include<bits/stdc++.h>
#define all(x) begin(x),end(x)

using namespace std;

using ll = long long;
using lll = __int128;
using ld = long double;
using pt = pair<int, int>;


int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int l, r;
    cin >> l >> r;
    vector<int> cnt(r + 1);
    for (int i = 1; i <= r; i++) {
        for (int j = i; j <= r; j += i) {
            cnt[j]++;
        }
    }
    vector<int> ans(r - l + 1);
    iota(all(ans), l);
    sort(all(ans), [&] (int a, int b) {
        return cnt[a] < cnt[b] || (cnt[a] == cnt[b] && a < b);
    });
    for (int val : ans) {
        cout << val << ' ';
    }
    cout << '\n';
}


// TASK 11
#include<bits/stdc++.h>
#define all(x) begin(x),end(x)

using namespace std;

using ll = long long;
using lll = __int128;
using ld = long double;
using pt = pair<int, int>;

ll dp[1 << 15];
pair<int,int> arr[15];

int Dist(int i, int j) {
    int dx = arr[i].first - arr[j].first;
    int dy = arr[i].second - arr[j].second;
    return dx * dx + dy * dy;
}

bool good(int i, int j, int k) {
    int dx1 = arr[i].first - arr[j].first;
    int dy1 = arr[i].second - arr[j].second;
    int dx2 = arr[i].first - arr[k].first;
    int dy2 = arr[i].second - arr[k].second;
    return dx1 * dy2 - dx2 * dy1 != 0;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int n;
    cin >> n;
    memset(dp, 0x3f, sizeof dp);
    for (int i = 0; i < n; i++) {
        cin >> arr[i].first >> arr[i].second;
    }
    for (int i = 0; i < n; i++) {
        for (int j = i + 1; j < n; j++) {
            for (int k = j + 1; k < n; k++) {
                int mask = (1 << i) | (1 << k) | (1 << j);
                int a = Dist(i, j);
                int b = Dist(i, k);
                int c = Dist(j, k);
                int cur = max({a, b, c});

                if (good(i, j, k)) {
                    dp[mask] = cur;
                }
            }
        }
    }
    // 2 ^ 15 * 15 * 15 * 15 / 6
    for (int mask = 0; mask < (1 << n); mask++) {
        int cnt = __builtin_popcount(mask);
        if (cnt < 3) continue;
        if (cnt % 3) continue;
        for (int i = 0; i < n; i++) {
            if (!((mask >> i) & 1)) continue;
            for (int j = i + 1; j < n; j++) {
                if (!((mask >> j) & 1)) continue;
                for (int k = j + 1; k < n; k++) {
                    if (!((mask >> k) & 1)) continue;
                    dp[mask] = min(dp[mask], max(dp[mask ^ (1 << i) ^ (1 << j) ^ (1 << k)], dp[(1 << i) ^ (1 << j) ^ (1 << k)]));
                }
            }
        }
    }
    ll res = dp[(1 << n) - 1];
    if (res > 1e9) {
        cout << -1 << '\n';
    } else {
        cout << fixed << setprecision(15) << sqrt(res) << '\n';
    }
}


// TASK 12
#include<bits/stdc++.h>
#define all(x) begin(x),end(x)

using namespace std;

using ll = long long;
using lll = __int128;
using ld = long double;
using pt = pair<int, int>;

const int N = 200200;

vector<int> g[N];
bool used[N];
int timer, tin[N], fup[N];
bool cut[N];

void Dfs(int v, int p) {
	used[v] = true;
	tin[v] = fup[v] = timer++;
	int children = 0;
	for (int to : g[v]) {
		if (to == p)  continue;
		if (used[to]) {
			fup[v] = min(fup[v], tin[to]);
		} else {
			Dfs(to, v);
			fup[v] = min (fup[v], fup[to]);
			if (fup[to] >= tin[v] && p != -1) {
                cut[v] = true;
            }
			++children;
		}
	}
	if (p == -1 && children > 1) {
        cut[v] = true;
    }
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int n;
    cin >> n;
    int m;
    cin >> m;
    vector<pair<int,int>> edges;
    for (int i = 0; i < m; i++) {
        int f, t;
        cin >> f >> t;
        f--, t--;
        g[f].push_back(t);
        g[t].push_back(f);
        edges.push_back({f, t});
    }
    Dfs(0, -1);
    vector<int> ans;
    for (int i = 0; i < m; i++) {
        auto& [f, t] = edges[i];
        if (cut[f] && cut[t]) {
            ans.push_back(i + 1);
        }
    }
    cout << ans.size() << '\n';
    for (int val : ans) {
        cout << val << ' ';
    }
    cout << '\n';
}