Merge pull request #409 from xirc/atcoder/typical90B

AtCoder/Typical90B

Author: xirc

atcoder/typical90/B/main.cpp

@@ -0,0 +1,51 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+using ll = int64_t;
+using ff = long double;
+
+map<int, vector<string>> cache;
+vector<string> solve(int N) {
+    if (N % 2 == 1) return {};
+    if (N == 0) {
+        return { "" };
+    }
+    if (cache.count(N)) {
+        return cache[N];
+    }
+
+    vector<string> ans;
+    for (auto const& s : solve(N-2)) {
+        ans.push_back("()" + s);
+        ans.push_back(s + "()");
+        ans.push_back("(" + s + ")");
+    }
+    for (int i = 2; i < N; i += 2) {
+        int j = N - i;
+        auto ls = solve(i);
+        auto rs = solve(j);
+        for (auto const& lhs : ls) {
+            for (auto const & rhs : rs) {
+                ans.push_back(lhs + rhs);
+            }
+        }
+    }
+    sort(ans.begin(), ans.end());
+    ans.erase(unique(ans.begin(), ans.end()), ans.end());
+
+    return cache[N] = ans;
+}
+
+int main() {
+    ios_base::sync_with_stdio(false);
+    cin.tie(0); cout.tie(0);
+
+    int N;
+    cin >> N;
+    auto ans = solve(N);
+    for (auto const& p : ans) {
+        cout << p << endl;
+    }
+
+    return 0;
+}