以下代码对数组进行二分查找。我完成了最困难的部分,并让代码在理论上可以工作;不幸的是,我无法从函数中返回值;
简而言之,我希望返回 'len' ;如果您在该行中设置断点,您将看到“len”包含正确的答案。但我错过了一些非常愚蠢的事情。请帮我鉴定一下。
var states = ['Alabama','Alaska','American Samoa','Arizona','Arkansas','California','Colorado','Connecticut','Delaware','District of Columbia','Federated States of Micronesia','Florida','Georgia','Guam','Hawaii','Idaho','Illinois','Indiana','Iowa','Kansas','Kentucky','Louisiana','Maine','Marshall Islands','Maryland','Massachusetts','Michigan','Minnesota','Mississippi','Missouri','Montana','Nebraska','Nevada','New Hampshire','New Jersey','New Mexico','New York','North Carolina','North Dakota','Northern Mariana Islands','Ohio','Oklahoma','Oregon','Palau','Pennsylvania','Puerto Rico','Rhode Island','South Carolina','South Dakota','Tennessee','Texas','Utah','Vermont','Virgin Island','Virginia','Washington','West Virginia','Wisconsin','Wyoming'];
function binarySearch(arr1,term){
var arr = [...arr1],
len = 0;
function helper(arr,term) {
if(arr.length > 1) {
if(arr[Math.floor(arr.length/2)] === term) {
len += Math.floor(arr.length/2);
return len;
}
if(arr[Math.floor(arr.length/2)] < term) {
len += Math.floor(arr.length/2);
arr.splice(0,Math.floor(arr.length/2));
helper(arr,term)
}
else if (arr[Math.floor(arr.length/2)] > term) {
arr.splice(Math.floor(arr.length/2),arr.length-1);
helper(arr,term)
}
} else {
return 'Element not found';
}
}
return helper(arr,term);
}
console.log(binarySearch(states,"Arizona"));
最佳答案
您的递归调用也应该返回给调用者:
替换:
helper(arr,term)
与:
return helper(arr,term)
在这两种情况下。
关于javascript - 从二分查找函数返回值,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/54667811/