Weird Array Problem

Question

I have the following code:

var possibilities = [["X"],["O"],["e"]];

var newPossibilities = [];

for (var i=0; i<3; i++) {
for (var j=0; j<possibilities.length; j++) {
newPossibilities.push(possibilities[j]);
}
}
//newPossibilities is now [["X"],["O"],["e"],["X"],["O"],["e"],["X"],["O"],["e"]];

newPossibilities[0].push("A");

console.log(newPossibilities);
//output: [["X", "A"],["O"],["e"],["X", "A"],["O"],["e"],["X", "A"],["O"],["e"]]

I'm wondering why the output is
[["X", "A"],["O"],["e"],["X", "A"],["O"],["e"],["X", "A"],["O"],["e"]]
and not
[["X", "A"],["O"],["e"],["X"],["O"],["e"],["X"],["O"],["e"]].
Can someone help me?

Answer 1

I found the solution here:

https://stackoverflow.com/questions/13565223/strange-array-push-in-js