获取最小数字

function getMinNum(str = '2354363463',n = 2){
    let arr = [];
    let splitArr = str.split('')
    for(let i = 0;i < splitArr.length - n + 1;i++){
        let item = splitArr.splice(i,n);
        arr.push(Number(splitArr.join('')));
        splitArr.splice(i,0,...item);
    }
    return Math.min(...arr);
}