tasks a-s

Task/Prime-decomposition/JavaScript/prime-decomposition-1.js

@@ -0,0 +1,39 @@
+function run_factorize(input, output) {
+    var n = new BigInteger(input.value, 10);
+    var TWO = new BigInteger("2", 10);
+    var divisor = new BigInteger("3", 10);
+    var prod = false;
+
+    if (n.compareTo(TWO) < 0)
+        return;
+
+    output.value = "";
+
+    while (true) {
+        var qr = n.divideAndRemainder(TWO);
+        if (qr[1].equals(BigInteger.ZERO)) {
+            if (prod)
+                output.value += "*";
+            else
+                prod = true;
+            output.value += "2";
+            n = qr[0];
+        }
+        else
+            break;
+    }
+
+    while (!n.equals(BigInteger.ONE)) {
+        var qr = n.divideAndRemainder(divisor);
+        if (qr[1].equals(BigInteger.ZERO)) {
+            if (prod)
+                output.value += "*";
+            else
+                prod = true;
+            output.value += divisor;
+            n = qr[0];
+        }
+        else
+            divisor = divisor.add(TWO);
+    }
+}

Task/Prime-decomposition/JavaScript/prime-decomposition-2.js

@@ -0,0 +1,41 @@
+function run_factorize(n) {
+	if (n <= 3)
+			return [n];
+
+	var ans = [];
+	var done = false;
+	while (!done)
+	{
+		if (n%2 === 0){
+				ans.push(2);
+				n /= 2;
+				continue;
+		}
+		if (n%3 === 0){
+				ans.push(3);
+				n /= 3;
+				continue;
+		}
+		if ( n === 1)
+			return ans;
+		var sr = Math.sqrt(n);
+		done = true;
+		// try to divide the checked number by all numbers till its square root.
+		for (var i=6; i<=sr; i+=6){
+				if (n%(i-1) === 0){ // is n divisible by i-1?
+						ans.push( (i-1) );
+						n /= (i-1);
+						done = false;
+						break;
+				}
+				if (n%(i+1) === 0){ // is n divisible by i+1?
+						ans.push( (i+1) );
+						n /= (i+1);
+						done = false;
+						break;
+				}
+		}
+	}
+	ans.push( n );
+	return ans;
+}