Solve some problems

6 files changed, 185 insertions, 0 deletions

diff --git a/codeforces/Coprime/main b/codeforces/Coprime/main
new file mode 100755
index 0000000..48c20d4
--- /dev/null
+++ b/codeforces/Coprime/main
diff --git a/codeforces/Coprime/main.cpp b/codeforces/Coprime/main.cpp
new file mode 100755
index 0000000..86cbd75
--- /dev/null
+++ b/codeforces/Coprime/main.cpp
@@ -0,0 +1,162 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+using ll = long long;
+using pii = pair<int, int>;
+using vpi = vector<pii>;
+using vi = vector<int>;
+using vll = vector<long long>;
+using mpii = map<int, int>;
+using mpll = map<ll, ll>;
+using db = long double;
+
+#define pb push_back 
+#define all(x) (x).begin(), (x).end()
+#define rall(x) (x).rbegin(), (x).rend()
+#define lb lower_bound
+#define ub upper_bound
+#define make_unique(x) sort(all((x))); (x).resize(unique(all((x))) - (x).begin())
+#define ceil(a, b) ((a) + (b) - 1) / (b))
+
+const int MOD = (int)1e9 + 7;
+const db PI = acos((db)-1);
+const int dx[4]{1, 0, -1, 0};
+const int dy[4]{0, 1, 0, -1};
+
+template<typename K, typename V> ostream& operator<<(ostream& os, const pair<K, V>& p);
+template<typename T> ostream& operator<<(ostream& os, const vector<T>& vec);
+template<typename K, typename V> ostream& operator<<(ostream& os, const map<K, V>& m);
+template<typename K, typename V> ostream& operator<<(ostream& os, const unordered_map<K, V>& m);
+template<typename T> ostream& operator<<(ostream& os, const set<T>& s);
+template<typename T> ostream& operator<<(ostream& os, const unordered_set<T>& s);
+
+template<typename K, typename V>
+ostream& operator<<(ostream& os, const pair<K, V>& p) {
+  os << "(" << p.first << ", " << p.second << ")";
+  return os;
+}
+
+template<typename T>
+ostream& operator<<(ostream& os, const vector<T>& vec) {
+  os << "{";
+  for (size_t i = 0; i < vec.size(); ++i) {
+    if (i > 0) os << ", ";
+    os << vec[i];
+  }
+  os << "}";
+  return os;
+}
+
+
+template<typename K, typename V>
+ostream& operator<<(ostream& os, const map<K, V>& m) {
+  os << "{";
+  for (const auto& p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template<typename K, typename V>
+ostream& operator<<(ostream& os, const unordered_map<K, V>& m) {
+  os << "{";
+  for (const auto& p : m) {
+    os << p.first << ": " << p.second << ", ";
+  }
+  os << "}";
+  return os;
+}
+
+template<typename T>
+ostream& operator<<(ostream& os, const set<T>& s) {
+  int i = 0;
+  os << "{";
+  for (const auto& e : s) {
+    if (i > 0) os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+template<typename T>
+ostream& operator<<(ostream& os, const unordered_set<T>& s) {
+  int i = 0;
+  os << "{";
+  for (const auto& e : s) {
+    if (i > 0) os << ", ";
+    os << e;
+    i++;
+  }
+  os << "}";
+  return os;
+}
+
+void print() {
+  cerr << "\n";
+}
+
+template<typename T, typename... TS>
+void print(T val, TS... vals) {
+  cerr << val << " ";
+  print(vals...);
+}
+
+
+
+/* stuff you should look for:
+  ---------------------------
+   * special cases (n=1?)
+   * int overflow, array bounds
+   * do smth instead of nothing and stay organized
+   * WRITE STUFF DOWN
+   * DON'T GET STUCK ON ONE APPROACH
+ */
+
+bool isPrime(int x) {
+  if (x == 2) return true;
+  for (int i = 2; i * i < x; i++) {
+    if (x % i == 0) {
+      return false;
+    }
+  }
+  return true;
+}
+
+void solve() {
+  int n;
+  cin >> n;
+  vi v(n);
+  unordered_map<int, int> mp;
+  int mx = 0;
+  int mn = INT_MAX;
+  for (int i = 0; i < n; i++) {
+    cin >> v[i];
+    mp[v[i]] = max(i + 1, mp[v[i]]);
+    mx = max(mx, v[i]);
+    mn = min(mn, v[i]);
+  }
+  int ans = -1;
+  for (int i = mn; i <= mx; i++) {
+    for (int j = mn; j <= mx; j++) {
+      if (__gcd(i, j) == 1 && (mp[i] != 0 && mp[j] != 0)) {
+        ans = max(ans, mp[i] + mp[j]);
+      }
+    }
+  }
+  cout << ans << '\n';
+}
+
+int main () {
+  ios_base::sync_with_stdio(false);
+  cin.tie(NULL);
+  int tt;
+  cin >> tt;
+  while(tt--) {
+    solve();
+  }
+}
+
+
diff --git a/codeforces/Coprime/main_input0.txt b/codeforces/Coprime/main_input0.txt
new file mode 100644
index 0000000..148fb06
--- /dev/null
+++ b/codeforces/Coprime/main_input0.txt
@@ -0,0 +1,13 @@
+6
+3
+3 2 1
+7
+1 3 5 2 4 7 7
+5
+1 2 3 4 5
+3
+2 2 4
+6
+5 4 3 15 12 16
+5
+1 2 2 3 6
diff --git a/codeforces/Coprime/main_input1.txt b/codeforces/Coprime/main_input1.txt
new file mode 100644
index 0000000..d213bc4
--- /dev/null
+++ b/codeforces/Coprime/main_input1.txt
@@ -0,0 +1,3 @@
+1
+3
+2 2 4
\ No newline at end of file
diff --git a/codeforces/Coprime/main_output0.txt b/codeforces/Coprime/main_output0.txt
new file mode 100644
index 0000000..9c9fc88
--- /dev/null
+++ b/codeforces/Coprime/main_output0.txt
@@ -0,0 +1,6 @@
+6
+12
+9
+-1
+10
+7
diff --git a/codeforces/Coprime/main_output1.txt b/codeforces/Coprime/main_output1.txt
new file mode 100644
index 0000000..d7d17fc
--- /dev/null
+++ b/codeforces/Coprime/main_output1.txt
@@ -0,0 +1 @@
+-1
\ No newline at end of file