الگوریتم ساده بهینه برای جستجوی الگو — راهنمای کاربردی

1/* C++ program for A modified Naive Pattern Searching  
2algorithm that is optimized for the cases when all  
3characters of pattern are different */
4#include <bits/stdc++.h> 
5using namespace std; 
6  
7/* A modified Naive Pettern Searching 
8algorithn that is optimized for the 
9cases when all characters of pattern are different */
10void search(string pat, string txt)  
11{  
12    int M = pat.size();  
13    int N = txt.size();  
14    int i = 0;  
15  
16    while (i <= N - M)  
17    {  
18        int j;  
19  
20        /* For current index i, check for pattern match */
21        for (j = 0; j < M; j++)  
22            if (txt[i + j] != pat[j])  
23                break;  
24  
25        if (j == M) // if pat[0...M-1] = txt[i, i+1, ...i+M-1]  
26        {  
27            cout << "Pattern found at index " << i << endl;  
28            i = i + M;  
29        }  
30        else if (j == 0)  
31            i = i + 1;  
32        else
33            i = i + j; // slide the pattern by j  
34    }  
35}  
36  
37/* Driver code*/
38int main()  
39{  
40    string txt = "ABCEABCDABCEABCD";  
41    string pat = "ABCD";  
42    search(pat, txt);  
43    return 0;  
44}  
45  
46// This code is contributed by rathbhupendra 

1/* C program for A modified Naive Pattern Searching 
2  algorithm that is optimized for the cases when all 
3  characters of pattern are different */
4#include<stdio.h> 
5#include<string.h> 
6  
7/* A modified Naive Pettern Searching algorithn that is optimized 
8   for the cases when all characters of pattern are different */
9void search(char pat[], char txt[]) 
10{ 
11    int M = strlen(pat); 
12    int N = strlen(txt); 
13    int i = 0; 
14  
15    while (i <= N - M) 
16    { 
17        int j; 
18  
19        /* For current index i, check for pattern match */
20        for (j = 0; j < M; j++) 
21            if (txt[i+j] != pat[j]) 
22                break; 
23  
24        if (j == M)  // if pat[0...M-1] = txt[i, i+1, ...i+M-1] 
25        { 
26           printf("Pattern found at index %d \n", i); 
27           i = i + M; 
28        } 
29        else if (j == 0) 
30           i = i + 1; 
31        else
32           i = i + j; // slide the pattern by j 
33    } 
34} 
35  
36/* Driver program to test above function */
37int main() 
38{ 
39   char txt[] = "ABCEABCDABCEABCD"; 
40   char pat[] = "ABCD"; 
41   search(pat, txt); 
42   return 0; 
43}

1/* Java program for A modified Naive Pattern Searching  
2algorithm that is optimized for the cases when all  
3characters of pattern are different */
4  
5class GFG 
6{ 
7      
8/* A modified Naive Pettern Searching 
9algorithn that is optimized for the 
10cases when all characters of pattern are different */
11static void search(String pat, String txt)  
12{  
13    int M = pat.length();  
14    int N = txt.length();  
15    int i = 0;  
16  
17    while (i <= N - M)  
18    {  
19        int j;  
20  
21        /* For current index i, check for pattern match */
22        for (j = 0; j < M; j++)  
23            if (txt.charAt(i + j) != pat.charAt(j))  
24                break;  
25  
26        if (j == M) // if pat[0...M-1] = txt[i, i+1, ...i+M-1]  
27        {  
28            System.out.println("Pattern found at index "+i);  
29            i = i + M;  
30        }  
31        else if (j == 0)  
32            i = i + 1;  
33        else
34            i = i + j; // slide the pattern by j  
35    }  
36}  
37  
38/* Driver code*/
39public static void main (String[] args)  
40{ 
41    String txt = "ABCEABCDABCEABCD";  
42    String pat = "ABCD";  
43    search(pat, txt);  
44}  
45} 
46  
47// This code is contributed by chandan_jnu 

1# Python program for A modified Naive Pattern Searching 
2# algorithm that is optimized for the cases when all 
3# characters of pattern are different 
4def search(pat, txt): 
5    M = len(pat) 
6    N = len(txt) 
7    i = 0
8  
9    while i <= N-M: 
10        # For current index i, check for pattern match 
11        for j in xrange(M): 
12            if txt[i+j] != pat[j]: 
13                break
14            j += 1
15  
16        if j==M:    # if pat[0...M-1] = txt[i,i+1,...i+M-1] 
17            print "Pattern found at index " + str(i) 
18            i = i + M 
19        elif j==0: 
20            i = i + 1
21        else: 
22            i = i+ j    # slide the pattern by j 
23  
24# Driver program to test the above function 
25txt = "ABCEABCDABCEABCD"
26pat = "ABCD"
27search(pat, txt) 
28  
29# This code is contributed by Bhavya Jain 

1/* C# program for A modified Naive Pattern Searching  
2algorithm that is optimized for the cases when all  
3characters of pattern are different */
4  
5using System; 
6  
7class GFG 
8{ 
9      
10/* A modified Naive Pettern Searching 
11algorithn that is optimized for the 
12cases when all characters of pattern are different */
13static void search(string pat, string txt)  
14{  
15    int M = pat.Length;  
16    int N = txt.Length;  
17    int i = 0;  
18  
19    while (i <= N - M)  
20    {  
21        int j;  
22  
23        /* For current index i, check for pattern match */
24        for (j = 0; j < M; j++)  
25            if (txt[i + j] != pat[j])  
26                break;  
27  
28        if (j == M) // if pat[0...M-1] = txt[i, i+1, ...i+M-1]  
29        {  
30            Console.WriteLine("Pattern found at index "+i);  
31            i = i + M;  
32        }  
33        else if (j == 0)  
34            i = i + 1;  
35        else
36            i = i + j; // slide the pattern by j  
37    }  
38}  
39  
40/* Driver code*/
41static void Main()  
42{  
43    string txt = "ABCEABCDABCEABCD";  
44    string pat = "ABCD";  
45    search(pat, txt);  
46}  
47} 
48  
49// This code is contributed by chandan_jnu 

1<?php 
2// PHP program for A modified Naive  
3// Pattern Searching algorithm that 
4// is optimized for the cases when all 
5// characters of pattern are different  
6  
7/* A modified Naive Pettern Searching 
8   algorithn that is optimized for the 
9   cases when all characters of  
10   pattern are different */
11function search($pat, $txt) 
12{ 
13    $M = strlen($pat); 
14    $N = strlen($txt); 
15    $i = 0; 
16  
17    while ($i <= $N - $M) 
18    { 
19        $j; 
20  
21        /* For current index i,  
22           check for pattern match */
23        for ($j = 0; $j < $M; $j++) 
24            if ($txt[$i + $j] != $pat[$j]) 
25                break; 
26  
27        // if pat[0...M-1] =  
28        // txt[i, i+1, ...i+M-1] 
29        if ($j == $M)  
30        { 
31            echo("Pattern found at index $i"."\n" ); 
32            $i = $i + $M; 
33        } 
34        else if ($j == 0) 
35            $i = $i + 1; 
36        else
37          
38            // slide the pattern by j 
39            $i = $i + $j;  
40    } 
41} 
42  
43// Driver Code 
44$txt = "ABCEABCDABCEABCD"; 
45$pat = "ABCD"; 
46search($pat, $txt); 
47  
48// This code is contributed by nitin mittal. 
49?>