Add all the A tasks

Task/Averages-Simple-moving-average/JavaScript/averages-simple-moving-average.js

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+function simple_moving_averager(period) {
+    var nums = [];
+    return function(num) {
+        nums.push(num);
+        if (nums.length > period)
+            nums.splice(0,1);  // remove the first element of the array
+        var sum = 0;
+        for (var i in nums)
+            sum += nums[i];
+        var n = period;
+        if (nums.length < period)
+            n = nums.length;
+        return(sum/n);
+    }
+}
+
+var sma3 = simple_moving_averager(3);
+var sma5 = simple_moving_averager(5);
+var data = [1,2,3,4,5,5,4,3,2,1];
+for (var i in data) {
+    var n = data[i];
+    // using WSH
+    WScript.Echo("Next number = " + n + ", SMA_3 = " + sma3(n) + ", SMA_5 = " + sma5(n));
+}