Added 4 CodeChef solutions

4 Problems Solutions : 
DANCEMOVES.cpp
MINLCM1.cpp
ROOTTREE.cpp
RRR.cpp

Author: ayush-rudani

Codechef solutions/(CODECHEF) DANCEMOVES.cpp

@@ -0,0 +1,41 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define ll long long
+#define endl "\n"
+const ll INF = 1e9 + 7;
+
+void solve()
+{
+    int x, y;
+    cin >> x >> y;
+
+    if (x == y)
+    {
+        cout << "0\n";
+    }
+    else if (x < y)
+    {
+        if (abs(y - x) % 2 == 0)
+            cout << abs(y - x) / 2 << endl;
+
+        else
+        {
+            int c = (abs(y - x) + 2 - 1) / 2;
+            cout << c + 1 << endl;
+        }
+    }
+    else
+        cout << abs(x - y) << endl;
+}
+
+int main()
+{
+    ios_base ::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    int T;
+    cin >> T;
+    while (T--)
+        solve();
+    return 0;
+}

Codechef solutions/(CODECHEF) MINLCM1.cpp

@@ -0,0 +1,25 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define ll long long
+#define endl "\n"
+const ll INF = 1e9 + 7;
+
+void solve()
+{
+    ll x, k;
+    cin >> x >> k;
+
+    cout << 2 * x << ' ' << x * k * (x * k - 1) << '\n';
+}
+
+int main()
+{
+    ios_base ::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    int T;
+    cin >> T;
+    while (T--)
+        solve();
+    return 0;
+}

Codechef solutions/(CODECHEF) ROOTTREE.cpp

@@ -0,0 +1,38 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define ll long long
+#define endl "\n"
+const ll INF = 1e9 + 7;
+
+void solve()
+{
+    int n;
+    cin >> n;
+    vector<int> in_degree(n + 1, 0);
+
+    for (int i = 0; i < n - 1; i++)
+    {
+        int u, v;
+        cin >> u >> v;
+        in_degree[v]++;
+    }
+
+    int cnt = 0;
+    for (int i = 1; i <= n; i++)
+        if (in_degree[i] == 0)
+            cnt++;
+
+    cout << cnt - 1 << endl;
+}
+
+int main()
+{
+    ios_base ::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    int T;
+    cin >> T;
+    while (T--)
+        solve();
+    return 0;
+}

Codechef solutions/(CODECHEF) RRR.cpp

@@ -0,0 +1,26 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define ll long long
+#define endl "\n"
+const ll INF = 1e9 + 7;
+
+void solve()
+{
+    int n, k;
+    cin >> n >> k;
+
+    int ans = 2 * (n - k) + (2 * ((k - 1) / 2));
+    cout << ans << '\n';
+}
+
+int main()
+{
+    ios_base ::sync_with_stdio(false);
+    cin.tie(NULL);
+
+    int T;
+    cin >> T;
+    while (T--)
+        solve();
+    return 0;
+}