Initial data commit

Task/Casting-out-nines/JavaScript/casting-out-nines-1.js

@@ -0,0 +1,47 @@
+function main(s, e, bs, pbs) {
+    bs = bs || 10;
+    pbs = pbs || 10
+    document.write('start:', toString(s), ' end:', toString(e),
+        ' base:', bs, ' printBase:', pbs)
+    document.write('<br>castOutNine: ');
+    castOutNine()
+    document.write('<br>kaprekar: ');
+    kaprekar()
+    document.write('<br><br>')
+
+    function castOutNine() {
+        for (var n = s, k = 0, bsm1 = bs - 1; n <= e; n += 1)
+            if (n % bsm1 == (n * n) % bsm1) k += 1,
+                document.write(toString(n), ' ')
+        document.write('<br>trying ', k, ' numbers instead of ', n = e - s + 1,
+            ' numbers saves ', (100 - k / n * 100)
+            .toFixed(3), '%')
+    }
+
+    function kaprekar() {
+        for (var n = s; n <= e; n += 1)
+            if (isKaprekar(n)) document.write(toString(n), ' ')
+
+        function isKaprekar(n) {
+            if (n < 1) return false
+            if (n == 1) return true
+            var s = (n * n)
+                .toString(bs)
+            for (var i = 1, e = s.length; i < e; i += 1) {
+                var a = parseInt(s.substr(0, i), bs)
+                var b = parseInt(s.substr(i), bs)
+                if (b && a + b == n) return true
+            }
+            return false
+        }
+    }
+
+    function toString(n) {
+        return n.toString(pbs)
+            .toUpperCase()
+    }
+}
+main(1, 10 * 10 - 1)
+main(1, 16 * 16 - 1, 16)
+main(1, 17 * 17 - 1, 17)
+main(parseInt('10', 17), parseInt('gg', 17), 17, 17)