arr.reduce(fuction(pre,cur,index,arr){},init)
1.数组去重
[1,2,31,1,3,2,4].reduce(function(pre,cur){
pre.indexOf(cur) === -1 && pre.push(cur);
return pre;
},[]);
2.求数组最大(最小)
[1,2,3,4,5].reduce(function(pre,cur){
return Math.max(pre,cur);
})
3.求数组和
[1,2,3,4].reduce(function(pre,cur){
return pre+cur;
},0)原文:https://www.cnblogs.com/yejiang/p/11834679.html