initial commit of Binary Addition

greedy_algorithms/binary_addition.cpp

@@ -0,0 +1,92 @@
+#include <iostream>
+#include <string>
+#include <algorithm>
+#include <cassert>
+
+/**
+ * A class to perform binary addition of two binary strings.
+ */
+class Solution {
+public:
+    /**
+     * Adds two binary strings and returns the result as a binary string.
+     *
+     * @param a The first binary string.
+     * @param b The second binary string.
+     * @return The sum of the two binary strings as a binary string.
+     */
+    std::string addBinary(const std::string& a, const std::string& b) {
+        std::string result;
+        int carry = 0;
+        int maxLength = std::max(a.size(), b.size());
+
+        // Traverse both strings from the end to the beginning
+        for (int i = 0; i < maxLength; ++i) {
+            // Get the current bits from both strings, if available
+            int bitA = (i < a.size()) ? (a[a.size() - 1 - i] - '0') : 0;
+            int bitB = (i < b.size()) ? (b[b.size() - 1 - i] - '0') : 0;
+
+            // Calculate the sum of bits and carry
+            int sum = bitA + bitB + carry;
+            carry = sum / 2; // Determine the carry for the next bit
+            result.push_back((sum % 2) + '0'); // Append the sum's current bit to result
+        }
+
+        // If there's still a carry left, append it
+        if (carry) {
+            result.push_back('1');
+        }
+
+        // The result is built in reverse order, so reverse it before returning
+        std::reverse(result.begin(), result.end());
+        return result;
+    }
+};
+
+/**
+ * Function to run tests for the addBinary method.
+ */
+void runTests() {
+    Solution solution;
+
+    // Test case for two binary strings of equal length without any carry over.
+    assert(solution.addBinary("1010", "1101") == "10111");
+
+    // Test case for two binary strings of equal length with a carry over.
+    assert(solution.addBinary("1111", "1111") == "11110");
+
+    // Test case for two binary strings where one is longer than the other.
+    assert(solution.addBinary("101", "11") == "1000");
+
+    // Test case for a binary string of all zeros.
+    assert(solution.addBinary("0", "0") == "0");
+
+    // Test case where both binary strings consist of all ones.
+    assert(solution.addBinary("1111", "1111") == "11110");
+
+    // Test case where one binary string is zero and the other is non-zero.
+    assert(solution.addBinary("0", "10101") == "10101");
+    assert(solution.addBinary("10101", "0") == "10101");
+
+    // Test case for large binary numbers with many digits.
+    assert(solution.addBinary("101010101010101010101010101010", "110110110110110110110110110110") == "1100001100001100001100001100000");
+
+    // Test case where one binary string is much longer than the other.
+    assert(solution.addBinary("1", "11111111") == "100000000");
+
+    // Test case for adding empty strings (edge case).
+    assert(solution.addBinary("", "") == "0");
+
+    // Test case where both binary strings consist of alternating ones and zeros.
+    assert(solution.addBinary("10101010", "01010101") == "11111111");
+
+    std::cout << "All tests passed!" << std::endl;
+}
+
+/**
+ * Main function to execute the program.
+ */
+int main() {
+    runTests();
+    return 0;
+}