Initial data commit

Task/Sum-to-100/JavaScript/sum-to-100-3.js

@@ -0,0 +1,122 @@
+SumTo100();
+
+function SumTo100()
+{
+    var
+        ADD  = 0,
+        SUB  = 1,
+        JOIN = 2;
+
+    var
+        nexpr = 13122;
+
+    function out(something)
+    {
+        WScript.Echo(something);
+    }
+
+    function evaluate(code)
+    {
+        var
+            value  = 0,
+            number = 0,
+            power  = 1;
+
+        for ( var k = 9; k >= 1; k-- )
+        {
+            number = power*k + number;
+            switch( code % 3 )
+            {
+                case ADD:  value = value + number; number = 0; power = 1; break;
+                case SUB:  value = value - number; number = 0; power = 1; break;
+                case JOIN: power = power * 10                           ; break;
+            }
+            code = Math.floor(code/3);
+        }
+        return value;
+    }
+
+    function print(code)
+    {
+        var
+            s = "";
+        var
+            a = 19683,
+            b = 6561;
+
+        for ( var k = 1; k <= 9; k++ )
+        {
+            switch( Math.floor(  (code % a) / b  ) ){
+                case ADD: if ( k > 1 ) s = s + '+'; break;
+                case SUB:              s = s + '-'; break;
+            }
+            a = b;
+            b = Math.floor(b/3);
+            s = s + String.fromCharCode(0x30+k);
+        }
+        out(evaluate(code) + " = " + s);
+    }
+
+    function comment(commentString)
+    {
+        out("");
+        out(commentString);
+        out("");
+    }
+
+    comment("Show all solutions that sum to 100");
+    for ( var i = 0; i < nexpr; i++)
+        if ( evaluate(i) == 100 )
+            print(i);
+
+    comment("Show the sum that has the maximum number of solutions");
+    var stat = {};
+    for ( var i = 0; i < nexpr; i++ )
+    {
+        var sum = evaluate(i);
+        if (stat[sum])
+            stat[sum]++;
+        else
+            stat[sum] = 1;
+    }
+
+    var best = 0;
+    var nbest = -1;
+    for ( var i = 0; i < nexpr; i++ )
+    {
+        var sum = evaluate(i);
+        if ( sum > 0 )
+            if ( stat[sum] > nbest )
+            {
+                best = i;
+                nbest = stat[sum];
+            }
+    }
+    out("" + evaluate(best) + " has " + nbest + " solutions");
+
+    comment("Show the lowest positive number that can't be expressed");
+    for ( var i = 0; i <= 123456789; i++ )
+    {
+        for ( var j = 0; j < nexpr; j++)
+            if ( i == evaluate(j) ) break;
+        if ( i != evaluate(j) ) break;
+    }
+    out(i);
+
+    comment("Show the ten highest numbers that can be expressed");
+    var limit = 123456789 + 1;
+    for ( i = 1; i <= 10; i++ )
+    {
+        var best = 0;
+        for ( var j = 0; j < nexpr; j++)
+        {
+            var test = evaluate(j);
+            if ( test < limit && test > best )
+                best = test;
+        }
+        for ( var j = 0; j < nexpr; j++)
+            if ( evaluate(j) == best ) print(j);
+        limit = best;
+    }
+
+}