433. Minimum Genetic Mutation

1function minMutation(startGene: string, endGene: string, bank: string[]): number {
2    const bank_set = new Set(bank);
3    if (!bank_set.has(endGene)) return -1;
4    const vis: Set<string> = new Set();
5    const queue: [string, number][] = [[startGene, 0]]
6    const genes = ['A', 'C', 'G', 'T']
7    while (queue.length) {
8        const [curr, steps] = queue.shift()!;
9        if (curr === endGene) return steps;
10        for (let i = 0; i < curr.length; i++) {
11            for (const g of genes) {
12                const mutated = curr.slice(0, i) + g + curr.slice(i + 1)
13                if (bank_set.has(mutated) && !vis.has(mutated)) {
14                    vis.add(mutated);
15                    queue.push([mutated, steps + 1])
16                }
17            }
18        }
19    }
20
21    return -1;
22}