برنامه پیدا کردن k نزدیک ترین عنصر به یک مقدار – راهنمای کاربردی

1#include<stdio.h> 
2  
3/* Function to find the cross over point (the point before 
4   which elements are smaller than or equal to x and after 
5   which greater than x)*/
6int findCrossOver(int arr[], int low, int high, int x) 
7{ 
8  // Base cases 
9  if (arr[high] <= x) // x is greater than all 
10    return high; 
11  if (arr[low] > x)  // x is smaller than all 
12    return low; 
13  
14  // Find the middle point 
15  int mid = (low + high)/2;  /* low + (high - low)/2 */
16  
17  /* If x is same as middle element, then return mid */
18  if (arr[mid] <= x && arr[mid+1] > x) 
19    return mid; 
20  
21  /* If x is greater than arr[mid], then either arr[mid + 1] 
22    is ceiling of x or ceiling lies in arr[mid+1...high] */
23  if(arr[mid] < x) 
24      return findCrossOver(arr, mid+1, high, x); 
25  
26  return findCrossOver(arr, low, mid - 1, x); 
27} 
28  
29// This function prints k closest elements to x in arr[]. 
30// n is the number of elements in arr[] 
31void printKclosest(int arr[], int x, int k, int n) 
32{ 
33    // Find the crossover point 
34    int l = findCrossOver(arr, 0, n-1, x); 
35    int r = l+1;   // Right index to search 
36    int count = 0; // To keep track of count of elements already printed 
37  
38    // If x is present in arr[], then reduce left index 
39    // Assumption: all elements in arr[] are distinct 
40    if (arr[l] == x) l--; 
41  
42    // Compare elements on left and right of crossover 
43    // point to find the k closest elements 
44    while (l >= 0 && r < n && count < k) 
45    { 
46        if (x - arr[l] < arr[r] - x) 
47            printf("%d ", arr[l--]); 
48        else
49            printf("%d ", arr[r++]); 
50        count++; 
51    } 
52  
53    // If there are no more elements on right side, then 
54    // print left elements 
55    while (count < k && l >= 0) 
56        printf("%d ", arr[l--]), count++; 
57  
58    // If there are no more elements on left side, then 
59    // print right elements 
60    while (count < k && r < n) 
61        printf("%d ", arr[r++]), count++; 
62} 
63  
64/* Driver program to check above functions */
65int main() 
66{ 
67   int arr[] ={12, 16, 22, 30, 35, 39, 42, 
68               45, 48, 50, 53, 55, 56}; 
69   int n = sizeof(arr)/sizeof(arr[0]); 
70   int x = 35, k = 4; 
71   printKclosest(arr, x, 4, n); 
72   return 0; 
73}

1// Java program to find k closest elements to a given value 
2class KClosest 
3{ 
4    /* Function to find the cross over point (the point before 
5       which elements are smaller than or equal to x and after 
6       which greater than x)*/
7    int findCrossOver(int arr[], int low, int high, int x) 
8    { 
9        // Base cases 
10        if (arr[high] <= x) // x is greater than all 
11            return high; 
12        if (arr[low] > x)  // x is smaller than all 
13            return low; 
14  
15        // Find the middle point 
16        int mid = (low + high)/2;  /* low + (high - low)/2 */
17  
18        /* If x is same as middle element, then return mid */
19        if (arr[mid] <= x && arr[mid+1] > x) 
20            return mid; 
21  
22        /* If x is greater than arr[mid], then either arr[mid + 1] 
23          is ceiling of x or ceiling lies in arr[mid+1...high] */
24        if(arr[mid] < x) 
25            return findCrossOver(arr, mid+1, high, x); 
26  
27        return findCrossOver(arr, low, mid - 1, x); 
28    } 
29  
30    // This function prints k closest elements to x in arr[]. 
31    // n is the number of elements in arr[] 
32    void printKclosest(int arr[], int x, int k, int n) 
33    { 
34        // Find the crossover point 
35        int l = findCrossOver(arr, 0, n-1, x);  
36        int r = l+1;   // Right index to search 
37        int count = 0; // To keep track of count of elements 
38                       // already printed 
39  
40        // If x is present in arr[], then reduce left index 
41        // Assumption: all elements in arr[] are distinct 
42        if (arr[l] == x) l--; 
43  
44        // Compare elements on left and right of crossover 
45        // point to find the k closest elements 
46        while (l >= 0 && r < n && count < k) 
47        { 
48            if (x - arr[l] < arr[r] - x) 
49                System.out.print(arr[l--]+" "); 
50            else
51                System.out.print(arr[r++]+" "); 
52            count++; 
53        } 
54  
55        // If there are no more elements on right side, then 
56        // print left elements 
57        while (count < k && l >= 0) 
58        { 
59            System.out.print(arr[l--]+" "); 
60            count++; 
61        } 
62  
63  
64        // If there are no more elements on left side, then 
65        // print right elements 
66        while (count < k && r < n) 
67        { 
68            System.out.print(arr[r++]+" "); 
69            count++; 
70        } 
71    } 
72  
73    /* Driver program to check above functions */
74    public static void main(String args[]) 
75    { 
76        KClosest ob = new KClosest(); 
77        int arr[] = {12, 16, 22, 30, 35, 39, 42, 
78                     45, 48, 50, 53, 55, 56
79                    }; 
80        int n = arr.length; 
81        int x = 35, k = 4; 
82        ob.printKclosest(arr, x, 4, n); 
83    } 
84} 
85/* This code is contributed by Rajat Mishra */

1# Function to find the cross over point  
2# (the point before which elements are  
3# smaller than or equal to x and after  
4# which greater than x)  
5def findCrossOver(arr, low, high, x) :  
6  
7    # Base cases  
8    if (arr[high] <= x) : # x is greater than all  
9        return high 
10          
11    if (arr[low] > x) : # x is smaller than all  
12        return low  
13      
14    # Find the middle point  
15    mid = (low + high) // 2 # low + (high - low)// 2  
16      
17    # If x is same as middle element,  
18    # then return mid  
19    if (arr[mid] <= x and arr[mid + 1] > x) : 
20        return mid  
21      
22    # If x is greater than arr[mid], then  
23    # either arr[mid + 1] is ceiling of x  
24    # or ceiling lies in arr[mid+1...high]  
25    if(arr[mid] < x) : 
26        return findCrossOver(arr, mid + 1, high, x) 
27      
28    return findCrossOver(arr, low, mid - 1, x) 
29  
30# This function prints k closest elements to x  
31# in arr[]. n is the number of elements in arr[]  
32def printKclosest(arr, x, k, n) : 
33      
34    # Find the crossover point  
35    l = findCrossOver(arr, 0, n - 1, x) 
36    r = l + 1 # Right index to search  
37    count = 0 # To keep track of count of  
38              # elements already printed  
39  
40    # If x is present in arr[], then reduce  
41    # left index. Assumption: all elements  
42    # in arr[] are distinct  
43    if (arr[l] == x) : 
44        l -= 1
45  
46    # Compare elements on left and right of crossover  
47    # point to find the k closest elements  
48    while (l >= 0 and r < n and count < k) : 
49          
50        if (x - arr[l] < arr[r] - x) : 
51            print(arr[l], end = " ")  
52            l -= 1
53        else : 
54            print(arr[r], end = " ")  
55            r += 1
56        count += 1
57  
58    # If there are no more elements on right  
59    # side, then print left elements  
60    while (count < k and l >= 0) : 
61        print(arr[l], end = " ") 
62        l -= 1
63        count += 1
64  
65    # If there are no more elements on left  
66    # side, then print right elements  
67    while (count < k and r < n) :  
68        print(arr[r], end = " ") 
69        r += 1
70        count += 1
71  
72# Driver Code 
73if __name__ == "__main__" : 
74  
75    arr =[12, 16, 22, 30, 35, 39, 42,  
76              45, 48, 50, 53, 55, 56] 
77                  
78    n = len(arr) 
79    x = 35
80    k = 4
81      
82    printKclosest(arr, x, 4, n) 
83      
84# This code is contributed by Ryuga

1// C# program to find k closest elements to 
2// a given value 
3using System; 
4  
5class GFG { 
6      
7    /* Function to find the cross over point  
8    (the point before which elements are 
9    smaller than or equal to x and after which 
10    greater than x)*/
11    static int findCrossOver(int []arr, int low, 
12                                int high, int x) 
13    { 
14          
15        // Base cases 
16        // x is greater than all 
17        if (arr[high] <= x) 
18            return high; 
19              
20        // x is smaller than all 
21        if (arr[low] > x)  
22            return low; 
23  
24        // Find the middle point 
25        /* low + (high - low)/2 */
26        int mid = (low + high)/2;  
27  
28        /* If x is same as middle element, then 
29        return mid */
30        if (arr[mid] <= x && arr[mid+1] > x) 
31            return mid; 
32  
33        /* If x is greater than arr[mid], then  
34        either arr[mid + 1] is ceiling of x or 
35        ceiling lies in arr[mid+1...high] */
36        if(arr[mid] < x) 
37            return findCrossOver(arr, mid+1,  
38                                      high, x); 
39  
40        return findCrossOver(arr, low, mid - 1, x); 
41    } 
42  
43    // This function prints k closest elements  
44    // to x in arr[]. n is the number of  
45    // elements in arr[] 
46    static void printKclosest(int []arr, int x, 
47                                  int k, int n) 
48    { 
49          
50        // Find the crossover point 
51        int l = findCrossOver(arr, 0, n-1, x);  
52          
53        // Right index to search 
54        int r = l + 1;  
55          
56        // To keep track of count of elements 
57        int count = 0;  
58  
59        // If x is present in arr[], then reduce  
60        // left index Assumption: all elements in 
61        // arr[] are distinct 
62        if (arr[l] == x) l--; 
63  
64        // Compare elements on left and right of  
65        // crossover point to find the k closest 
66        // elements 
67        while (l >= 0 && r < n && count < k) 
68        { 
69            if (x - arr[l] < arr[r] - x) 
70                Console.Write(arr[l--]+" "); 
71            else
72                Console.Write(arr[r++]+" "); 
73            count++; 
74        } 
75  
76        // If there are no more elements on right  
77        // side, then print left elements 
78        while (count < k && l >= 0) 
79        { 
80            Console.Write(arr[l--]+" "); 
81            count++; 
82        } 
83  
84        // If there are no more elements on left  
85        // side, then print right elements 
86        while (count < k && r < n) 
87        { 
88            Console.Write(arr[r++] + " "); 
89            count++; 
90        } 
91    } 
92  
93    /* Driver program to check above functions */
94    public static void Main() 
95    { 
96        int []arr = {12, 16, 22, 30, 35, 39, 42, 
97                         45, 48, 50, 53, 55, 56}; 
98        int n = arr.Length; 
99        int x = 35; 
100        printKclosest(arr, x, 4, n); 
101    } 
102} 
103  
104// This code is contributed by nitin mittal.

1<?php 
2// PHP Program to Find k closest  
3// elements to a given value 
4  
5/* Function to find the cross  
6   over point (the point before 
7   which elements are smaller  
8   than or equal to x and after 
9   which greater than x) */
10function findCrossOver($arr, $low,  
11                       $high, $x) 
12{ 
13      
14    // Base cases 
15      
16    // x is greater than all 
17    if ($arr[$high] <= $x)  
18        return $high; 
19          
20    // x is smaller than all 
21    if ($arr[$low] > $x)  
22        return $low; 
23      
24    // Find the middle point 
25    /* low + (high - low)/2 */
26    $mid = ($low + $high)/2;  
27      
28    /* If x is same as middle  
29       element, then return mid */
30    if ($arr[$mid] <= $x and
31        $arr[$mid + 1] > $x) 
32        return $mid; 
33      
34    /* If x is greater than arr[mid],  
35       then either arr[mid + 1] is  
36       ceiling of x or ceiling lies  
37       in arr[mid+1...high] */
38    if($arr[$mid] < $x) 
39        return findCrossOver($arr, $mid + 1,  
40                                 $high, $x); 
41      
42    return findCrossOver($arr, $low, 
43                      $mid - 1, $x); 
44} 
45  
46// This function prints k 
47// closest elements to x in arr[]. 
48// n is the number of elements  
49// in arr[] 
50function printKclosest($arr, $x, $k, $n) 
51{ 
52      
53    // Find the crossover point 
54    $l = findCrossOver($arr, 0, $n - 1, $x); 
55      
56    // Right index to search 
57    $r = $l + 1; 
58      
59    // To keep track of count of 
60    // elements already printed 
61    $count = 0;  
62  
63    // If x is present in arr[],  
64    // then reduce left index 
65    // Assumption: all elements  
66    // in arr[] are distinct 
67    if ($arr[$l] == $x) $l--; 
68  
69    // Compare elements on left  
70    // and right of crossover 
71    // point to find the k  
72    // closest elements 
73    while ($l >= 0 and $r < $n 
74              and $count < $k) 
75    { 
76        if ($x - $arr[$l] < $arr[$r] - $x) 
77            echo $arr[$l--]," "; 
78        else
79            echo $arr[$r++]," "; 
80        $count++; 
81    } 
82  
83    // If there are no more 
84    // elements on right side, 
85    // then print left elements 
86    while ($count < $k and $l >= 0) 
87        echo $arr[$l--]," "; $count++; 
88  
89    // If there are no more  
90    // elements on left side,  
91    // then print right elements 
92    while ($count < $k and $r < $n) 
93        echo $arr[$r++]; $count++; 
94} 
95  
96// Driver Code 
97$arr =array(12, 16, 22, 30, 35, 39, 42, 
98                45, 48, 50, 53, 55, 56); 
99$n = count($arr); 
100$x = 35; $k = 4; 
101  
102printKclosest($arr, $x, 4, $n); 
103  
104// This code is contributed by anuj_67. 
105?>