tasks a-s

Task/Non-decimal-radices-Convert/D/non-decimal-radices-convert-1.d

@@ -0,0 +1,8 @@
+import std.stdio, std.conv, std.string;
+
+void main() {
+    "1abcd".to!int(16).writeln();
+
+    toLower(60_272_032_366.to!string(36) ~ " " ~
+            591_458.to!string(36)).writeln();
+}

Task/Non-decimal-radices-Convert/D/non-decimal-radices-convert-2.d

@@ -0,0 +1,62 @@
+import std.stdio, std.array, std.ascii;
+
+enum string mDigits = "0123456789abcdefghijklmnopqrstuvwxyz";
+
+ulong atoiRadix(in string str, in int radix=10, int* consumed=null) {
+    static int dtoi(in char dc, in int radix) {
+        static int[immutable char] digit;
+        immutable char d = cast(char)toLower(dc);
+        if (digit.length == 0) // not init yet
+            foreach (i, c; mDigits)
+                digit[c] = i;
+        if (radix > 1 && radix <= digit.length &&
+            d in digit && digit[d] < radix)
+            return digit[d];
+        return int.min; // a negative for error.
+    }
+
+    ulong result;
+    int sp;
+    for (; sp < str.length; sp++) {
+        immutable int d = dtoi(str[sp], radix);
+        if (d >= 0) // valid digit char
+            result = radix * result + d;
+        else
+            break;
+    }
+    if (sp != str.length) // some char in str not converted.
+        sp = -sp;
+    if (consumed !is null) // signal error if not positive.
+        *consumed = sp;
+    return result;
+}
+
+string itoaRadix(ulong num, in int radix=10) pure nothrow
+in {
+    assert(radix > 1 && radix <= mDigits.length);
+} body {
+    string result;
+    while (num > 0) {
+        //immutable int d = num % radix;
+        immutable int d = cast(int)(num % radix);
+        result = mDigits[d] ~ result;
+        num = (num - d) / radix;
+    }
+    return result.empty ? "0" : result;
+}
+
+void main() {
+    immutable string numStr = "1ABcdxyz???";
+
+    int ate;
+    writef("'%s' (base %d) = %d", numStr, 16,
+           atoiRadix(numStr, 16, &ate));
+
+    if (ate <= 0)
+        writefln("\tConverted only: '%s'", numStr[0 .. -ate]);
+    else
+        writeln();
+
+    writeln(itoaRadix(60_272_032_366, 36), " ",
+            itoaRadix(591_458, 36));
+}