rna_transcription: iteration 1

cpp/rna-transcription/rna_transcription.cpp

@@ -0,0 +1,25 @@
+#include "rna_transcription.h"
+
+#include <algorithm>
+#include <unordered_map>
+
+namespace transcription {
+
+using namespace std;
+
+char to_rna(char c)
+{
+    static const unordered_map<char, char> nucleotide_map =
+        {{'C', 'G'}, {'G', 'C'}, {'A', 'U'}, {'T', 'A'}};
+
+    return nucleotide_map.at(c);
+}
+
+string to_rna(string str)
+{
+    transform(str.begin(), str.end(), str.begin(),
+            static_cast<char (*)(char)>(&to_rna));
+    return str;
+}
+
+}