solution.js

/**
 * @param {number[]} arr
 * @return {number}
 */
var minJumps = function (arr) {
    const groupByNode = arr.reduce((obj, item, index) => {
        if (!obj[item]) {
            obj[item] = [];
        }
        obj[item].push(index);
        return obj;
    }, {});
    const minSteps = new Array(arr.length).fill(Infinity);
    minSteps[0] = 0;
    const queue = [
        0, ];
    while (queue.length) {
        const index = queue.shift();
        // 探索临边
        if (index > 0 && minSteps[index - 1] > minSteps[index] + 1) {
            minSteps[index - 1] = minSteps[index] + 1;
            queue.push(index - 1);
        }
        if (index < arr.length - 1 && minSteps[index + 1] > minSteps[index] + 1) {
            minSteps[index + 1] = minSteps[index] + 1;
            queue.push(index + 1);
        }
        const sameIndexs = groupByNode[arr[index]];
        for (let i = 0; i < sameIndexs.length; i++) {
            const rIndex = sameIndexs[i];
            if (minSteps[rIndex] > minSteps[index] + 1) {
                minSteps[rIndex] = minSteps[index] + 1;
                queue.push(rIndex);
            }
        }
    }

    return minSteps[arr.length - 1];
};