add AtCoder

Author: lzyrapx

AtCoder/abc139/.vscode/settings.json

@@ -0,0 +1,5 @@
+{
+    "files.associations": {
+        "ostream": "cpp"
+    }
+}

AtCoder/abc139/A - Tenki.cpp

@@ -0,0 +1,19 @@
+#include <bits/stdc++.h>
+using namespace std;
+string s;
+string t;
+int main()
+{
+    cin >> t;
+    cin >> s;
+    int cnt = 0;
+    for (int i = 0; i < t.size(); i++)
+    {
+        if (s[i] == t[i])
+        {
+            cnt++;
+        }
+    }
+    cout << cnt << endl;
+    return 0;
+}

AtCoder/abc139/B - Power Socket.cpp

@@ -0,0 +1,24 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+int main()
+{
+    int a, b;
+    cin >> a >> b;
+    if (b <= 1)
+    {
+        cout << 0 << endl;
+        exit(0);
+    }
+    int now = 1;
+    int ans = 0;
+    while (now < b)
+    {
+        ans += 1;
+        now -= 1;
+        now += a;
+    }
+    cout << ans << endl;
+    return 0;
+}

AtCoder/abc139/C - Lower.cpp

@@ -0,0 +1,29 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+int main()
+{
+    int n;
+    cin >> n;
+    int v;
+    cin >> v;
+    int tmp = v;
+    int ans = 0, cnt = 0;
+    for (int i = 1; i < n; i++)
+    {
+        cin >> v;
+        if (v <= tmp)
+        {
+            cnt += 1;
+            tmp = v;
+        }
+        else
+        {
+            cnt = 0;
+            tmp = v;
+        }
+        ans = max(ans, cnt);
+    }
+    cout << ans << endl;
+    return 0;
+}

AtCoder/abc139/D - ModSum.cpp

@@ -0,0 +1,14 @@
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+// {1, 2, 3} => {3, 1, 2} => 3
+// {1, 2, 3 4 } => {4, 1, 2, 3} => 6
+int main()
+{
+    long long n;
+    cin >> n;
+    cout << n * (n - 1) / 2 << endl;
+    return 0;
+}

AtCoder/abc139/E - League.cpp

@@ -0,0 +1,102 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+const int maxn = 1234;
+vector<int> edge[maxn * maxn], tmp[maxn * maxn];
+
+/*
+ 2 -> 3 <- 1
+ ^         | 
+ |         |
+  _ _ _ _ _
+
+ 2 -> 3    1
+ ^         |  
+ |         |
+  _ _ _ _ _
+
+topoSort to check cycle + longest path on the path, O(n^2)
+*/
+int color[maxn * maxn];
+int dp[maxn * maxn];
+
+bool dfs1(int u)
+{
+    if (color[u] == 2)
+        return true;
+    color[u] = 1; // visited
+    for (auto v : edge[u])
+    {
+        if (color[v] > 0)
+        {
+            if (color[v] == 1)
+                return false; // cycle
+        }
+        if (!dfs1(v))
+        {
+            return false;
+        }
+    }
+    color[u] = 2;
+    return true;
+}
+
+int dfs2(int u)
+{
+    if (dp[u])
+    {
+        return dp[u];
+    }
+    int cnt = 0;
+    for (auto v : edge[u])
+    {
+        cnt = max(cnt, dfs2(v));
+    }
+    dp[u] = cnt + 1;
+    return dp[u];
+}
+int main()
+{
+    int n;
+    cin >> n;
+    for (int i = 1; i <= n; i++)
+    {
+        for (int j = 0; j < n - 1; j++)
+        {
+            int a;
+            cin >> a;
+            tmp[i].push_back(a);
+        }
+    }
+    for (int i = 1; i <= n; i++)
+    {
+        for (int j = 1; j < n - 1; j++)
+        {
+            int r1 = i, c1 = tmp[i][j - 1];
+            int r2 = i, c2 = tmp[i][j];
+            if (r1 > c1)
+                swap(r1, c1);
+            if (r2 > c2)
+                swap(r2, c2);
+            int s = r1 * n + c1;
+            int t = r2 * n + c2;
+            edge[s].push_back(t);
+        }
+    }
+    for (int i = 0; i < n * n; i++)
+    {
+        if (color[i] == 0 && !dfs1(i))
+        {
+            cout << "-1" << endl;
+            exit(0);
+        }
+    }
+    int ans = 0;
+    for (int i = 0; i < n * n; i++)
+    {
+        ans = max(ans, dfs2(i));
+    }
+    cout << ans << endl;
+    return 0;
+}

AtCoder/abc139/F - Engines.cpp

@@ -0,0 +1,41 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+const int maxn = 1e4;
+struct node
+{
+    int x, y;
+} point[maxn];
+
+bool cmp(node a, node b)
+{
+    return atan2(a.x, a.y) < atan2(b.x, b.y);
+}
+int main()
+{
+    int n;
+    cin >> n;
+    for (int i = 0; i < n; i++)
+    {
+        cin >> point[i].x >> point[i].y;
+    }
+    long long ans = 0;
+    int tx, ty;
+    sort(point, point + n, cmp);
+    for (int i = 0; i < n; i++)
+    {
+        tx = point[i].x;
+        ty = point[i].y;
+        ans = max(ans, 1LL * tx * tx + 1LL * ty * ty);
+        for (int j = (i + 1) % n; j != i; j = (j + 1) % n)
+        {
+            tx += point[j].x;
+            ty += point[j].y;
+            ans = max(ans, 1LL * tx * tx + 1LL * ty * ty);
+        }
+    }
+    double res = sqrt(ans);
+    printf("%.13f\n", res);
+    return 0;
+}