binary: initial commit

cpp/binary/binary.cpp

@@ -0,0 +1,31 @@
+#include "binary.h"
+
+namespace binary {
+
+unsigned convert(const std::string &input)
+{
+    unsigned result = 0;
+    unsigned factor = 1;
+
+    for (auto i = input.crbegin(); i != input.crend(); ++i) {
+
+        switch (*i) {
+
+        case '0':
+            break;
+
+        case '1':
+            result += factor;
+            break;
+
+        default:
+            return 0;
+        }
+
+        factor <<= 1;
+    }
+
+    return result;
+}
+
+}

cpp/binary/binary.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#define EXERCISM_RUN_ALL_TESTS
+
+#include <string>
+
+namespace binary {
+
+unsigned int convert(const std::string&);
+
+}