Merge pull request #309 from xirc/atcoder/abc070

AtCoder/ABC070

Author: xirc

atcoder/abc070/A/main.cpp

@@ -0,0 +1,20 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+using ll = long long;
+
+int main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(0); cout.tie(0);
+
+    string N;
+    cin >> N;
+
+    if (N[0] == N[2]) {
+        cout << "Yes" << endl;
+    } else {
+        cout << "No" << endl;
+    }
+
+    return 0;
+}

atcoder/abc070/B/main.cpp

@@ -0,0 +1,18 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+using ll = long long;
+
+int main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(0); cout.tie(0);
+
+    int A, B, C, D;
+    cin >> A >> B >> C >> D;
+
+    int L = max(A, C), R = min(B, D);
+    int ans = max(0, R - L);
+    cout << ans << endl;
+
+    return 0;
+}

atcoder/abc070/C/main.cpp

@@ -0,0 +1,41 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+using ll = long long;
+
+int N;
+vector<ll> T;
+
+ll gcd(ll a, ll b) {
+    while (b > 0) {
+        ll c = a % b;
+        a = b, b = c;
+    }
+    return a;
+}
+
+ll lcm(ll a, ll b) {
+    return a / gcd(a, b) * b;
+}
+
+ll solve() {
+    ll ans = 1;
+    for (auto t : T) {
+        ans = lcm(ans, t);
+    }
+    return ans;
+}
+
+int main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(0); cout.tie(0);
+
+    cin >> N;
+    T.assign(N, 0);
+    for (int i = 0; i < N; ++i) {
+        cin >> T[i];
+    }
+    cout << solve() << endl;
+
+    return 0;
+}

atcoder/abc070/D/main.cpp

@@ -0,0 +1,54 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+using ll = long long;
+
+struct edge { int to; int w; };
+int N, K;
+vector<vector<edge>> G;
+
+vector<ll> ds;
+void dfs(int v, int p) {
+    for (auto const& e : G[v]) {
+        if (e.to == p) continue;
+        ds[e.to] = ds[v] + e.w;
+        dfs(e.to, v);
+    }
+}
+
+void build() {
+    ds.assign(N, 0);
+    dfs(K, K);
+}
+
+ll query(int x, int y) { 
+    return ds[x] + ds[y];
+}
+
+int main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(0); cout.tie(0);
+
+    cin >> N;
+    G.assign(N, vector<edge>());
+    for (int i = 0; i < N - 1; ++i) {
+        int a, b, c;
+        cin >> a >> b >> c;
+        --a, --b;
+        G[a].push_back({ b, c });
+        G[b].push_back({ a, c });
+    }
+
+    int Q;
+    cin >> Q >> K;
+    --K;
+    build();
+    for (int i = 0; i < Q; ++i) {
+        int x, y;
+        cin >> x >> y;
+        --x, --y;
+        cout << query(x, y) << endl;
+    }
+
+    return 0;
+}