From 21d3875b481cce42c361400143d0421192e84497 Mon Sep 17 00:00:00 2001
From: Harsh Dev Pathak <harshoxfordgkp@gmail.com>
Date: Sun, 8 Oct 2023 10:40:23 +0530
Subject: [PATCH] feat:add graycode algorithm

---
 bit_manipulation/gray_code.cpp | 60 ++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 bit_manipulation/gray_code.cpp

diff --git a/bit_manipulation/gray_code.cpp b/bit_manipulation/gray_code.cpp
new file mode 100644
index 000000000..1359075e8
--- /dev/null
+++ b/bit_manipulation/gray_code.cpp
@@ -0,0 +1,60 @@
+#include <cassert>
+#include <iostream>
+#include <vector>
+
+using namespace std;
+
+/**
+ * Function to generate Gray code sequence for 'n' bits.
+ *
+ * @param n - The number of bits for which to generate Gray code.
+ * @return A vector of strings representing the Gray code sequence.
+ */
+vector<string> generateGrayCode(int n) {
+    if (n == 1) {
+        vector<string> grayCode;
+        grayCode.push_back("0");
+        grayCode.push_back("1");
+        return grayCode;
+    }
+    vector<string> prevGrayCode = generateGrayCode(n - 1);
+
+    vector<string> grayCode;
+    for (int i = 0; i < prevGrayCode.size(); i++) {
+        grayCode.push_back("0" + prevGrayCode[i]);
+    }
+    for (int i = prevGrayCode.size() - 1; i >= 0; i--) {
+        grayCode.push_back("1" + prevGrayCode[i]);
+    }
+
+    return grayCode;
+}
+
+/**
+ * Test function for Gray code generation.
+ *
+ * This function tests the generateGrayCode function with various test cases
+ * and uses the assert function to check if the generated sequence matches
+ * the expected sequence.
+ */
+
+void testGrayCodeGeneration() {
+    vector<pair<int, vector<string>>> testCases = {
+        {1, {"0", "1"}},
+        {2, {"00", "01", "11", "10"}},
+        {3, {"000", "001", "011", "010", "110", "111", "101", "100"}},
+    };
+
+    for (const auto& testCase : testCases) {
+        int n = testCase.first;
+        const vector<string>& expected = testCase.second;
+        vector<string> result = generateGrayCode(n);
+        assert(result == expected);
+        cout << "Test for " << n << " bits passed!" << endl;
+    }
+}
+
+int main() {
+    testGrayCodeGeneration();
+    return 0;
+}