Calculations added

src/main/logic/Calculations.kt

+package logic
+
+public class Calculations {
+    public static fun strSlice(str: String) : ArrayList<Int> {
+        val arraylist = ArrayList<Integer>()
+        for (i: Int; i < str.length; i++) {
+            if(str[i] < '9' && str[i] >= '0')
+                arraylist.add(str[i] - '0');
+        }
+        return arraylist
+    }
+}
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