How to search a 2D array inside a 2D array efficiently?

I am trying to search a 2D array inside a 2D array, and I have tried the following code to do so:

loopX: for (int x = 0; x < str1.length - str2.length + 1; ++x)

            loopY: for (int y = 0; y < str1[x].length - str2[0].length + 1; ++y)

            {

                for (int xx = 0; xx < str2.length; ++xx)

                for (int yy = 0; yy < str2[0].length; ++yy)

                {

                    if (str1[x + xx][y + yy] != str2[xx][yy])

                    {

                        k++;

                        continue loopY;



                    }

                }



                // Found the submatrix!

                System.out.println("Found at: " + x + " " + y);

                break loopX;

            }

            System.out.println(k);

In this code str1 is the larger 2D array inside which I am trying to search and match the smaller 2D array str2. Both are char arrays.

k is the element I need to keep track of in case, there is no match.

I would also like to know what can be the most efficient way to do so.

For this the algorithm I thought, that first I should match only the starting element of both the arrays, and when they match then only go and match other elements.

But, I am not able to write specific code for this.

I would appreciate if someone could help me in this.

asked Nov 24 '18 at 8:17

user10516751

Please see this answer. stackoverflow.com/a/34119138/5774004

– Sreeragh A R
Nov 24 '18 at 8:30

@SreeraghAR that answer didn't help, I tried that method.

– user10516751
Nov 24 '18 at 8:45

add a comment |

I am trying to search a 2D array inside a 2D array, and I have tried the following code to do so:

loopX: for (int x = 0; x < str1.length - str2.length + 1; ++x)

            loopY: for (int y = 0; y < str1[x].length - str2[0].length + 1; ++y)

            {

                for (int xx = 0; xx < str2.length; ++xx)

                for (int yy = 0; yy < str2[0].length; ++yy)

                {

                    if (str1[x + xx][y + yy] != str2[xx][yy])

                    {

                        k++;

                        continue loopY;



                    }

                }



                // Found the submatrix!

                System.out.println("Found at: " + x + " " + y);

                break loopX;

            }

            System.out.println(k);

In this code str1 is the larger 2D array inside which I am trying to search and match the smaller 2D array str2. Both are char arrays.

k is the element I need to keep track of in case, there is no match.

I would also like to know what can be the most efficient way to do so.

For this the algorithm I thought, that first I should match only the starting element of both the arrays, and when they match then only go and match other elements.

But, I am not able to write specific code for this.

I would appreciate if someone could help me in this.

asked Nov 24 '18 at 8:17

user10516751

Please see this answer. stackoverflow.com/a/34119138/5774004

– Sreeragh A R
Nov 24 '18 at 8:30

@SreeraghAR that answer didn't help, I tried that method.

– user10516751
Nov 24 '18 at 8:45

add a comment |

I am trying to search a 2D array inside a 2D array, and I have tried the following code to do so:

loopX: for (int x = 0; x < str1.length - str2.length + 1; ++x)

            loopY: for (int y = 0; y < str1[x].length - str2[0].length + 1; ++y)

            {

                for (int xx = 0; xx < str2.length; ++xx)

                for (int yy = 0; yy < str2[0].length; ++yy)

                {

                    if (str1[x + xx][y + yy] != str2[xx][yy])

                    {

                        k++;

                        continue loopY;



                    }

                }



                // Found the submatrix!

                System.out.println("Found at: " + x + " " + y);

                break loopX;

            }

            System.out.println(k);

In this code str1 is the larger 2D array inside which I am trying to search and match the smaller 2D array str2. Both are char arrays.

k is the element I need to keep track of in case, there is no match.

I would also like to know what can be the most efficient way to do so.

For this the algorithm I thought, that first I should match only the starting element of both the arrays, and when they match then only go and match other elements.

But, I am not able to write specific code for this.

I would appreciate if someone could help me in this.

asked Nov 24 '18 at 8:17

user10516751

I am trying to search a 2D array inside a 2D array, and I have tried the following code to do so:

loopX: for (int x = 0; x < str1.length - str2.length + 1; ++x)

            loopY: for (int y = 0; y < str1[x].length - str2[0].length + 1; ++y)

            {

                for (int xx = 0; xx < str2.length; ++xx)

                for (int yy = 0; yy < str2[0].length; ++yy)

                {

                    if (str1[x + xx][y + yy] != str2[xx][yy])

                    {

                        k++;

                        continue loopY;



                    }

                }



                // Found the submatrix!

                System.out.println("Found at: " + x + " " + y);

                break loopX;

            }

            System.out.println(k);

In this code str1 is the larger 2D array inside which I am trying to search and match the smaller 2D array str2. Both are char arrays.

k is the element I need to keep track of in case, there is no match.

I would also like to know what can be the most efficient way to do so.

For this the algorithm I thought, that first I should match only the starting element of both the arrays, and when they match then only go and match other elements.

But, I am not able to write specific code for this.

I would appreciate if someone could help me in this.

java multidimensional-array

asked Nov 24 '18 at 8:17

user10516751

asked Nov 24 '18 at 8:17

user10516751

asked Nov 24 '18 at 8:17

user10516751

asked Nov 24 '18 at 8:17

user10516751

asked Nov 24 '18 at 8:17

user10516751

Please see this answer. stackoverflow.com/a/34119138/5774004

– Sreeragh A R
Nov 24 '18 at 8:30

@SreeraghAR that answer didn't help, I tried that method.

– user10516751
Nov 24 '18 at 8:45

add a comment |

Please see this answer. stackoverflow.com/a/34119138/5774004

– Sreeragh A R
Nov 24 '18 at 8:30

@SreeraghAR that answer didn't help, I tried that method.

– user10516751
Nov 24 '18 at 8:45

Please see this answer. stackoverflow.com/a/34119138/5774004

– Sreeragh A R
Nov 24 '18 at 8:30

@SreeraghAR that answer didn't help, I tried that method.

– user10516751
Nov 24 '18 at 8:45

add a comment |

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