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MARS
MARS
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char * tem[10]; // global
void merge(char * arr[], int s1, int e1, int s2, int e2)
{
    int index = s1;
    int k = s1; //record where to start for the for loop int the bottom
    while(s1 <= e1 && s2 <= e2)
    {
        int i = 0, j = 0;
        while(arr[s1][i] != '\0' && arr[s2][j] != '\0')
        { 
            //compare each character in the string

            if(arr[s1][i] < arr[s2][j])
            {
                tem[index] = arr[s1];
                s1++;
                index++;
                break;
            }
            else if(arr[s1][i] > arr[s2][j])
            {
                tem[index] = arr[s2];
                s2++;
                index++;
                break;
            }
            else
            {
                i++;
                j++;
            }
        }

        //if one string contains the other
        if(arr[s1][i] == '\0' && arr[s2][j] != '\0') //if the first string is shorter
        {
            tem[index] = arr[s1];
            s1++;
            index++;
        }
        else if(arr[s1][i] != '\0' && arr[s2][j] == '\0') //if the second one is shorter
        {
            tem[index] = arr[s2];
            s2++;
            index++;
        }
        else if(arr[s1][i] == '\0' && arr[s2][j] == '\0')//if two strings are equivalent
        {
            tem[index] = arr[s1];
            index++;
            s1++;
            tem[index] = arr[s2]; 
            index++;
            s2++;
        }
    }

    for(k; k <= e2; k++) //copy the temporarily stored array to array that we want to sort
        arr[k] = tem[k];
}

void merge_sort(char * arr[], int start, int end)
{
    if(start < end)
    {
        int mid = (start + end) / 2;
        merge_sort(arr, start, mid);
        merge_sort(arr, mid + 1, end);
        merge(arr, start, mid, mid + 1, end);
    }
} 

char * tem[10]; // global
void merge(char * arr[], int s1, int e1, int s2, int e2)
{
    int index = s1;
    int k = s1; //record where to start for the for loop int the bottom
    while(s1 <= e1 && s2 <= e2)
    {
        int i = 0, j = 0;
        while(arr[s1][i] != '\0' && arr[s2][j] != '\0')
        { 
            //compare each character in the string

            if(arr[s1][i] < arr[s2][j])
            {
                tem[index] = arr[s1];
                s1++;
                index++;
                break;
            }
            else if(arr[s1][i] > arr[s2][j])
            {
                tem[index] = arr[s2];
                s2++;
                index++;
                break;
            }
            else
            {
                i++;
                j++;
            }
        }

        //if one string contains the other
        if(arr[s1][i] == '\0' && arr[s2][j] != '\0') //if the first string is shorter
        {
            tem[index] = arr[s1];
            s1++;
            index++;
        }
        else if(arr[s1][i] != '\0' && arr[s2][j] == '\0') //if the second one is shorter
        {
            tem[index] = arr[s2];
            s2++;
            index++;
        }
        else if(arr[s1][i] == '\0' && arr[s2][j] == '\0')//if two strings are equivalent
        {
            tem[index] = arr[s1];
            index++;
            s1++;
            tem[index] = arr[s2];
            index++;
            s2++;
        }
    }

    for(k; k <= e2; k++) //copy the temporarily stored array to array that we want to sort
        arr[k] = tem[k];
}

void merge_sort(char * arr[], int start, int end)
{
    if(start < end)
    {
        int mid = (start + end) / 2;
        merge_sort(arr, start, mid);
        merge_sort(arr, mid + 1, end);
        merge(arr, start, mid, mid + 1, end);
    }
} 

char * tem[10]; // global
void merge(char * arr[], int s1, int e1, int s2, int e2)
{
    int index = s1;
    int k = s1; //record where to start for the for loop int the bottom
    while(s1 <= e1 && s2 <= e2)
    {
        int i = 0, j = 0;
        while(arr[s1][i] != '\0' && arr[s2][j] != '\0')
        { 
            //compare each character in the string

            if(arr[s1][i] < arr[s2][j])
            {
                tem[index] = arr[s1];
                s1++;
                index++;
                break;
            }
            else if(arr[s1][i] > arr[s2][j])
            {
                tem[index] = arr[s2];
                s2++;
                index++;
                break;
            }
            else
            {
                i++;
                j++;
            }
        }

        //if one string contains the other
        if(arr[s1][i] == '\0' && arr[s2][j] != '\0') //if the first string is shorter
        {
            tem[index] = arr[s1];
            s1++;
            index++;
        }
        else if(arr[s1][i] != '\0' && arr[s2][j] == '\0') //if the second one is shorter
        {
            tem[index] = arr[s2];
            s2++;
            index++;
        }
        else if(arr[s1][i] == '\0' && arr[s2][j] == '\0')//if two strings are equivalent
        {
            tem[index] = arr[s1];
            index++;
            s1++;
            tem[index] = arr[s2]; 
            index++;
            s2++;
        }
    }

    for(k; k <= e2; k++) //copy the temporarily stored array to array that we want to sort
        arr[k] = tem[k];
}

void merge_sort(char * arr[], int start, int end)
{
    if(start < end)
    {
        int mid = (start + end) / 2;
        merge_sort(arr, start, mid);
        merge_sort(arr, mid + 1, end);
        merge(arr, start, mid, mid + 1, end);
    }
}
added 359 characters in body
Source Link
Y_C
Y_C
  • 115
  • 1
  • 13
char * tem[10]; // global
void merge(char * arr[], int s1, int e1, int s2, int e2)
{
        int index = s1;
        int k = s1;
  //record where to start for the for loop int the bottom
    while(s1 <= e1 && s2 <= e2)
        {
            int i = 0, j = 0;
        while(arr[s1][i] != '\0' && arr[s2][j] != '\0')
        { 
            //compare each character in the string

            if(arr[s1][i] < arr[s2][j])
            {
                tem[index] = arr[s1];
                s1++;
                index++;
                break;
            }
            else if(arr[s1][i] > arr[s2][j])
            {
                tem[index] = arr[s2];
                s2++;
                index++;
                break;
            }
            else
            {
                i++;
                j++;
            }
        } 

        //if one string contains the other
        if(arr[s1][i] == '\0' && arr[s2][j] != '\0') //if the first string is shorter
        {
            tem[index] = arr[s1];
            s1++;
            index++;
        }
        else if(arr[s1][i] != '\0' && arr[s2][j] == '\0') //if the second one is shorter
        {
            tem[index] = arr[s2];
            s2++;
            index++;
        }
        else if(arr[s1][i] == '\0' && arr[s2][j] == '\0')//if two strings are equivalent
        {
            tem[index] = arr[s1];
            index++;
            s1++;
            tem[index] = arr[s2];
            index++;
            s2++;
        }
    }

    for(k; k <= e2; k++) //copy the temporarily stored array to array that we want to sort
        arr[k] = tem[k];
}

void merge_sort(char * arr[], int start, int end)
{
    if(start < end)
    {
        int mid = (start + end) / 2;
        merge_sort(arr, start, mid);
        merge_sort(arr, mid + 1, end);
        merge(arr, start, mid, mid + 1, end);
    }
}

I use "strcpy" to copy "foo" and "bar" to input[1] and input[2], and set input[0][3] and input[1][3] to '\0'

char * tem[10];
void merge(char * arr[], int s1, int e1, int s2, int e2)
{
        int index = s1;
        int k = s1;
         while(s1 <= e1 && s2 <= e2)
        {
            int i = 0, j = 0;
        while(arr[s1][i] != '\0' && arr[s2][j] != '\0')
        {
            if(arr[s1][i] < arr[s2][j])
            {
                tem[index] = arr[s1];
                s1++;
                index++;
                break;
            }
            else if(arr[s1][i] > arr[s2][j])
            {
                tem[index] = arr[s2];
                s2++;
                index++;
                break;
            }
            else
            {
                i++;
                j++;
            }
        }

        if(arr[s1][i] == '\0' && arr[s2][j] != '\0')
        {
            tem[index] = arr[s1];
            s1++;
            index++;
        }
        else if(arr[s1][i] != '\0' && arr[s2][j] == '\0')
        {
            tem[index] = arr[s2];
            s2++;
            index++;
        }
        else if(arr[s1][i] == '\0' && arr[s2][j] == '\0')
        {
            tem[index] = arr[s1];
            index++;
            s1++;
            tem[index] = arr[s2];
            index++;
            s2++;
        }
    }

    for(k; k <= e2; k++)
        arr[k] = tem[k];
}

void merge_sort(char * arr[], int start, int end)
{
    if(start < end)
    {
        int mid = (start + end) / 2;
        merge_sort(arr, start, mid);
        merge_sort(arr, mid + 1, end);
        merge(arr, start, mid, mid + 1, end);
    }
}

I use "strcpy" to copy "foo" and "bar" to input[1] and input[2]

char * tem[10]; // global
void merge(char * arr[], int s1, int e1, int s2, int e2)
{
    int index = s1;
    int k = s1; //record where to start for the for loop int the bottom
    while(s1 <= e1 && s2 <= e2)
    {
        int i = 0, j = 0;
        while(arr[s1][i] != '\0' && arr[s2][j] != '\0')
        { 
            //compare each character in the string

            if(arr[s1][i] < arr[s2][j])
            {
                tem[index] = arr[s1];
                s1++;
                index++;
                break;
            }
            else if(arr[s1][i] > arr[s2][j])
            {
                tem[index] = arr[s2];
                s2++;
                index++;
                break;
            }
            else
            {
                i++;
                j++;
            }
        } 

        //if one string contains the other
        if(arr[s1][i] == '\0' && arr[s2][j] != '\0') //if the first string is shorter
        {
            tem[index] = arr[s1];
            s1++;
            index++;
        }
        else if(arr[s1][i] != '\0' && arr[s2][j] == '\0') //if the second one is shorter
        {
            tem[index] = arr[s2];
            s2++;
            index++;
        }
        else if(arr[s1][i] == '\0' && arr[s2][j] == '\0')//if two strings are equivalent
        {
            tem[index] = arr[s1];
            index++;
            s1++;
            tem[index] = arr[s2];
            index++;
            s2++;
        }
    }

    for(k; k <= e2; k++) //copy the temporarily stored array to array that we want to sort
        arr[k] = tem[k];
}

void merge_sort(char * arr[], int start, int end)
{
    if(start < end)
    {
        int mid = (start + end) / 2;
        merge_sort(arr, start, mid);
        merge_sort(arr, mid + 1, end);
        merge(arr, start, mid, mid + 1, end);
    }
}

I use "strcpy" to copy "foo" and "bar" to input[1] and input[2], and set input[0][3] and input[1][3] to '\0'

Source Link
Y_C
Y_C
  • 115
  • 1
  • 13

Try to sort strings with merge sort

How do I sort a 2D-array(strings) using merge sort?

e.g.

arr[0] = "foo";
arr[1] = "bar";

and I hope it to be like

arr[0] = "bar";
arr[1] = "foo";

after being sorted but it doesn't work

Need some help here.

The following is my code for merge sort:

char * tem[10];
void merge(char * arr[], int s1, int e1, int s2, int e2)
{
        int index = s1;
        int k = s1;
        while(s1 <= e1 && s2 <= e2)
        {
            int i = 0, j = 0;
        while(arr[s1][i] != '\0' && arr[s2][j] != '\0')
        {
            if(arr[s1][i] < arr[s2][j])
            {
                tem[index] = arr[s1];
                s1++;
                index++;
                break;
            }
            else if(arr[s1][i] > arr[s2][j])
            {
                tem[index] = arr[s2];
                s2++;
                index++;
                break;
            }
            else
            {
                i++;
                j++;
            }
        }

        if(arr[s1][i] == '\0' && arr[s2][j] != '\0')
        {
            tem[index] = arr[s1];
            s1++;
            index++;
        }
        else if(arr[s1][i] != '\0' && arr[s2][j] == '\0')
        {
            tem[index] = arr[s2];
            s2++;
            index++;
        }
        else if(arr[s1][i] == '\0' && arr[s2][j] == '\0')
        {
            tem[index] = arr[s1];
            index++;
            s1++;
            tem[index] = arr[s2];
            index++;
            s2++;
        }
    }

    for(k; k <= e2; k++)
        arr[k] = tem[k];
}

void merge_sort(char * arr[], int start, int end)
{
    if(start < end)
    {
        int mid = (start + end) / 2;
        merge_sort(arr, start, mid);
        merge_sort(arr, mid + 1, end);
        merge(arr, start, mid, mid + 1, end);
    }
}

And this is my 2D-array

input[2][3];

I use "strcpy" to copy "foo" and "bar" to input[1] and input[2]

This is how I call the function:

 void merge_sort(input, 0, 1);

I think the problem might be the first parameter of the function "merge" since I'm not sure if I can pass the 2D-array as "char * []"...

Thanks!