upload

7.1/A.cpp

@@ -0,0 +1,40 @@
+#include <iostream>
+#include <string>
+#include <vector>
+
+typedef long long ll;
+
+void GrayCode(ll n) {
+  if (n <= 0) {
+    return;
+  }
+
+  std::vector<std::string> code;
+
+  code.push_back("0");
+  code.push_back("1");
+
+  ll i, j;
+
+  for (i = 2; i < (1 << n); i = i << 1) {
+    for (j = i - 1; j >= 0; j--) {
+      code.push_back(code[j]);
+    }
+    for (j = 0; j < i; j++) {
+      code[j] = "0" + code[j];
+    }
+    for (j = i; j < 2 * i; j++) {
+      code[j] = "1" + code[j];
+    }
+  }
+
+  for (i = 0; i < code.size(); i++)
+    std::cout << code[i] << std::endl;
+}
+
+int main() {
+  ll n;
+  std::cin >> n;
+  GrayCode(n);
+  return 0;
+}