Description
Given a sorted integer array arr, two integers k and x, return the k closest integers to x in the array. The result should also be sorted in ascending order.
An integer a is closer to x than an integer b if:
|a - x| < |b - x|, or|a - x| == |b - x| and a < b
Example 1:
Input: arr = [1,2,3,4,5], k = 4, x = 3
Output: [1,2,3,4]
Example 2:
Input: arr = [1,1,2,3,4,5], k = 4, x = -1
Output: [1,1,2,3]
Constraints:
1 <= k <= arr.length1 <= arr.length <= 104arr is sorted in ascending order.-104 <= arr[i], x <= 104
Solutions
Solution 1: Sort
PythonJavaC++GoTypeScriptRust
class Solution:
def findClosestElements(self, arr: List[int], k: int, x: int) -> List[int]:
arr.sort(key=lambda v: abs(v - x))
return sorted(arr[:k])(code-box)
class Solution {
public List<Integer> findClosestElements(int[] arr, int k, int x) {
List<Integer> ans = Arrays.stream(arr)
.boxed()
.sorted((a, b) -> {
int v = Math.abs(a - x) - Math.abs(b - x);
return v == 0 ? a - b : v;
})
.collect(Collectors.toList());
ans = ans.subList(0, k);
Collections.sort(ans);
return ans;
}
}(code-box)
int target;
class Solution {
public:
static bool cmp(int& a, int& b) {
int v = abs(a - target) - abs(b - target);
return v == 0 ? a < b : v < 0;
}
vector<int> findClosestElements(vector<int>& arr, int k, int x) {
target = x;
sort(arr.begin(), arr.end(), cmp);
vector<int> ans(arr.begin(), arr.begin() + k);
sort(ans.begin(), ans.end());
return ans;
}
};(code-box)
func findClosestElements(arr []int, k int, x int) []int {
sort.Slice(arr, func(i, j int) bool {
v := abs(arr[i]-x) - abs(arr[j]-x)
if v == 0 {
return arr[i] < arr[j]
}
return v < 0
})
ans := arr[:k]
sort.Ints(ans)
return ans
}
func abs(x int) int {
if x >= 0 {
return x
}
return -x
}(code-box)
function findClosestElements(arr: number[], k: number, x: number): number[] {
let l = 0;
let r = arr.length;
while (r - l > k) {
if (x - arr[l] <= arr[r - 1] - x) {
--r;
} else {
++l;
}
}
return arr.slice(l, r);
}(code-box)
impl Solution {
pub fn find_closest_elements(arr: Vec<i32>, k: i32, x: i32) -> Vec<i32> {
let n = arr.len();
let mut l = 0;
let mut r = n;
while r - l != (k as usize) {
if x - arr[l] <= arr[r - 1] - x {
r -= 1;
} else {
l += 1;
}
}
arr[l..r].to_vec()
}
}(code-box)
Solution 2: Binary search
PythonJavaC++GoTypeScriptRust
class Solution:
def findClosestElements(self, arr: List[int], k: int, x: int) -> List[int]:
l, r = 0, len(arr)
while r - l > k:
if x - arr[l] <= arr[r - 1] - x:
r -= 1
else:
l += 1
return arr[l:r](code-box)
class Solution {
public List<Integer> findClosestElements(int[] arr, int k, int x) {
int l = 0, r = arr.length;
while (r - l > k) {
if (x - arr[l] <= arr[r - 1] - x) {
--r;
} else {
++l;
}
}
List<Integer> ans = new ArrayList<>();
for (int i = l; i < r; ++i) {
ans.add(arr[i]);
}
return ans;
}
}(code-box)
class Solution {
public:
vector<int> findClosestElements(vector<int>& arr, int k, int x) {
int l = 0, r = arr.size();
while (r - l > k) {
if (x - arr[l] <= arr[r - 1] - x) {
--r;
} else {
++l;
}
}
return vector<int>(arr.begin() + l, arr.begin() + r);
}
};(code-box)
func findClosestElements(arr []int, k int, x int) []int {
l, r := 0, len(arr)
for r-l > k {
if x-arr[l] <= arr[r-1]-x {
r--
} else {
l++
}
}
return arr[l:r]
}(code-box)
function findClosestElements(arr: number[], k: number, x: number): number[] {
let left = 0;
let right = arr.length - k;
while (left < right) {
const mid = (left + right) >> 1;
if (x - arr[mid] <= arr[mid + k] - x) {
right = mid;
} else {
left = mid + 1;
}
}
return arr.slice(left, left + k);
}(code-box)
impl Solution {
pub fn find_closest_elements(arr: Vec<i32>, k: i32, x: i32) -> Vec<i32> {
let k = k as usize;
let n = arr.len();
let mut left = 0;
let mut right = n - k;
while left < right {
let mid = left + (right - left) / 2;
if x - arr[mid] > arr[mid + k] - x {
left = mid + 1;
} else {
right = mid;
}
}
arr[left..left + k].to_vec()
}
}(code-box)
Solution 3
PythonJavaC++Go
class Solution:
def findClosestElements(self, arr: List[int], k: int, x: int) -> List[int]:
left, right = 0, len(arr) - k
while left < right:
mid = (left + right) >> 1
if x - arr[mid] <= arr[mid + k] - x:
right = mid
else:
left = mid + 1
return arr[left : left + k](code-box)
class Solution {
public List<Integer> findClosestElements(int[] arr, int k, int x) {
int left = 0;
int right = arr.length - k;
while (left < right) {
int mid = (left + right) >> 1;
if (x - arr[mid] <= arr[mid + k] - x) {
right = mid;
} else {
left = mid + 1;
}
}
List<Integer> ans = new ArrayList<>();
for (int i = left; i < left + k; ++i) {
ans.add(arr[i]);
}
return ans;
}
}(code-box)
class Solution {
public:
vector<int> findClosestElements(vector<int>& arr, int k, int x) {
int left = 0, right = arr.size() - k;
while (left < right) {
int mid = (left + right) >> 1;
if (x - arr[mid] <= arr[mid + k] - x)
right = mid;
else
left = mid + 1;
}
return vector<int>(arr.begin() + left, arr.begin() + left + k);
}
};(code-box)
func findClosestElements(arr []int, k int, x int) []int {
left, right := 0, len(arr)-k
for left < right {
mid := (left + right) >> 1
if x-arr[mid] <= arr[mid+k]-x {
right = mid
} else {
left = mid + 1
}
}
return arr[left : left+k]
}(code-box)
