求一个数组的最大、最小值、平均值、求和

//求最大值和最小值
var tmp = [1,12,"-",5];
var max = tmp[0]=="-"?0:tmp[0];
var min= tmp[0]=="-"?0:tmp[0];
for(var i=1;i<tmp.length;i++){ 
    if(Number(max)=="-"||Number(tmp[i])=="")continue;
    if(Number(max)<Number(tmp[i]))
        max=tmp[i];
    if(Number(min)>Number(tmp[i]))
        min=tmp[i];
    }
console.log(max);
console.log(min);


//求平均值
var arr1=[11,2,"-",5];
var getSum=function(ar){
    var arr=ar    
    var   sum=arr.reduce(function(prev, curr, idx, arr){
                if(curr=="-"||curr=="")return parseFloat(prev)
                return parseFloat(prev) + parseFlaot(curr);
              },0)
        return  sum;
     }
  alert(  getSum(arr1));            //11

求和

function sum(arr) {
    var s = 0;
    for (var i=arr.length-1; i>=0; i--) {
        if(isNaN(arr[i])){
            s+=0;
        }else{
            s += arr[i];
        }
        
    }
    return s;
}