How can I determine all possible ways a subsequence can be removed from a sequence?

Question

Given two sequences, A and B, how can I generate a list of all the possible ways that B can be removed from A?

For example, In JavaSc

Answer 1

First I would use string. It's easier to manipulate:

var results = [];

function permute(arr) {
    var cur, memo = [];

    for (var i = 0; i < arr.length; i++) {
        cur = arr.splice(i, 1);
        if (arr.length === 0) {
            results.push(memo.concat(cur));
        }
        permute(arr.slice(), memo.concat(cur));
        arr.splice(i, 0, cur[0]);
    }
    return results;
}

function removeSub(arr, sub) {
    strArray = arr.join(' ');
    if(strArray.includes(sub)){
        return strArray.replace(sub.join(' ')).split(' ');
    }
    return [];
}

function removeSubSeq(arr, sub) {
    return permute(removeSub(arr, sub));
}

I have not commented the code, but do not hesitate to ask for clarification. It's not tested, but the idea is in it...