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Task/Ethiopian-multiplication/Sidef/ethiopian-multiplication.sidef

@@ -0,0 +1,14 @@
+func double (n) { n * 2 };
+func halve  (n) { int(n / 2) };
+
+func ethiopic_mult(a, b) {
+    var r = 0;
+    while (a > 0) {
+        a.is_even || (r += b);
+        a = halve(a);
+        b = double(b);
+    };
+    return r;
+}
+
+say ethiopic_mult(17, 34);