首頁猿問 input輸入時判定陣列值

input輸入時判定陣列值

JavaScript

幕布斯6054654 2019-05-12 08:54:06

我想在一個input透過陣列中使用二分搜尋,找到最相近的值,並在input變換成最相近的數值,該如何實現呢？假設陣列是[4,7,8]在input中輸入5他會自動變成4.求助大神！//二分搜尋法Array.prototype.binary_search=function(low,high,khey){if(low>high)return-1;varmid=parseInt((high+low)/2);if(this[mid]>khey)returnthis.binary_search(low,mid-1,khey);if(this[mid]

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MM們

TA貢獻1886條經驗獲得超2個贊

Array.prototype.binary_search=function(target,low,high){if(this.length<=1||target==null){returnthis[0]}low=low>=0?Math.min(low,this.length-1):0high=high>=0?Math.min(high,this.length-1):this.length-1if(low>high){[low,high]=[high,low]}if(low===high){returnthis[low]}constmid=(low+high)/2|0if(target===this[mid]){returntarget}if(targetif(target>=this[mid-1]){returnthis[mid]-target}else{returnthis.binary_search(target,low,mid-1)}}//if(target>this[mid]){if(target<=this[mid+1]){returntarget-this[mid]}else{returnthis.binary_search(target,mid+1,high)}//}};console.log([4,7,8].binary_search(5))//4console.log([4,7,8].binary_search(6))//7console.log([4,7,8].binary_search(7))//7console.log([4,7,8].binary_search(10000))//8console.log([4,7,8].binary_search(-1))//4console.log([4,7,8].binary_search())//4console.log([].binary_search())//undefinedconsole.log([].binary_search(5))//undefined

反對回復 2019-05-12

ABOUTYOU

TA貢獻1812條經驗獲得超5個贊

用迭代比較簡單，沒使用遞歸。Array.prototype.binary_search_clo=function(khey){varlow=0;varhigh=this.lengthvarmid=parseInt((high+low+1)/2);while(this[mid]!=khey&&lowif(this[mid]>khey){high=mid-1;}elseif(this[mid]low=mid+1;}mid=parseInt((high+low)/2);}if(mid>0&&Math.abs(parseInt(this[mid]-khey))>Math.abs(parseInt(this[mid-1]-khey))){mid=mid-1;}returnmid;};找到最后了，要與旁邊比較一下，哪個更接近。