done 3 sorting problems

CSES - CSES Problem Set/Introducotry_Problems/Gray_Code.cpp

@@ -0,0 +1,32 @@
+//  Gray Code
+
+#include<bits/stdc++.h>
+
+using namespace std;
+
+vector<string> gray_code(int size, bool print) {
+    if (size == 1) {
+        if (print) {
+            cout << "0" << '\n' << "1" << endl;
+        }
+        return {"0", "1"};
+    }
+    auto prev_gray_code = gray_code(size - 1, false);
+    vector<string> output;
+    for (auto &s: prev_gray_code) {
+        if (print) cout << "0"+s << endl;
+        output.push_back("0"+s);
+    }
+    std::reverse(prev_gray_code.begin(), prev_gray_code.end());
+    for (auto &s: prev_gray_code) {
+        if (print) cout << "1"+s << endl;
+        output.push_back("1"+s);
+    }
+    return output;
+}
+
+int main() {
+    int n; cin >> n;
+    gray_code(n, true);
+    return 0;
+}