tasks a-s

Task/Roman-numerals-Encode/D/roman-numerals-encode.d

@@ -0,0 +1,26 @@
+string toRoman(int n) pure nothrow
+in {
+    assert(n < 5000);
+} body {
+    static immutable weights = [1000, 900, 500, 400, 100, 90,
+                                50, 40, 10, 9, 5, 4, 1];
+    static immutable symbols = ["M","CM","D","CD","C","XC","L",
+                                "XL","X","IX","V","IV","I"];
+
+    string roman;
+    foreach (i, w; weights) {
+        while (n >= w) {
+            roman ~= symbols[i];
+            n -= w;
+        }
+        if (n == 0)
+            break;
+    }
+    return roman;
+} unittest {
+    assert(toRoman(455)  == "CDLV");
+    assert(toRoman(3456) == "MMMCDLVI");
+    assert(toRoman(2488) == "MMCDLXXXVIII");
+}
+
+void main() {}