Initial data commit

Task/Arrays/GAP/arrays.gap

@@ -0,0 +1,45 @@
+# Arrays are better called lists in GAP. Lists may have elements of mixed types, e$
+v := [ 10, 7, "bob", true, [ "inner", 5 ] ];
+# [ 10, 7, "bob", true, [ "inner", 5 ] ]
+
+# List index runs from 1 to Size(v)
+v[1];
+# 10
+
+v[0];
+# error
+
+v[5];
+# [ "inner", 5 ]
+
+v[6];
+# error
+
+# One can assign a value to an undefined element
+v[6] := 100;
+
+# Even if it's not after the last: a list may have undefined elements
+v[10] := 1000;
+v;
+# [ 10, 7, "bob", true, [ "inner", 5 ], 100,,,, 1000 ]
+
+# And one can check for defined values
+IsBound(v[10]);
+# true
+
+IsBound(v[9]);
+# false
+
+# Size of the list
+Size(v);
+# 10
+
+# Appending a list to the end of another
+Append(v, [ 8, 9]);
+v;
+# [ 10, 7, "bob", true, [ "inner", 5 ], 100,,,, 1000, 8, 9 ]
+
+# Adding an element at the end
+Add(v, "added");
+v;
+# [ 10, 7, "bob", true, [ "inner", 5 ], 100,,,, 1000, 8, 9, "added" ]