C Program to Concatenate Two Strings Lexically

/*  
 * C Program to Concatenate the given two Strings Lexically
 */
#include <string.h>
#include <stdio.h>
 
void sort(char *p);
 
void main()
{
    char string1[100], string2[100];
    int i, len, j;
 
    printf("\nEnter a string : ");
    scanf("%[^\n]s", string1);
    printf("\nEnter another string to concat : ");
    scanf(" %[^\n]s", string2);
    len = strlen(string1);
    string1[len] = ' ';
    for(i = 0, j = len + 1; i < strlen(string2); i++, j++)
        string1[j] = string2[i];
    string1[j]='\0';
    sort(string1);
}
 
/* Sorting to make concatenation lexical */
void sort(char *p)
{
    char temp[100];
    char a[100][100];
    int t1, i, j = 0, k = 0, l = strlen(p), x = 0, y = 0, z = 0, count, l1, l2;
 
    for (i = 0; i < l; i++)
    {
        if (p[i] != ' ') 
        {
            a[k][j++] = p[i];
        }
        else
        {
            a[k][j] = '\0';
            k++;
            j = 0;
        }
    }
 
    t1 = k;
    k = 0;
 
    for (i = 0; i < t1; i++)
    {
        for (j = i + 1; j <= t1; j++)
        {
            l1 = strlen(a[i]);
            l2 = strlen(a[j]);
            if (l1 > l2)
                count = l1;
            else
                count = l2;
            x = 0, y = 0;
            while ((x < count) || (y < count))
            {
                if (a[i][x] == a[j][y])
                {
                    x++;
                    y++;
                    continue;
                }
                else 
                    if (a[i][x] < a[j][y]) break;
                else 
                    if (a[i][x] > a[j][y])
                    {
                        for (z = 0; z < l2; z++)
                        {
                            temp[z] = a[j][z];
                            a[j][z] = '\0';
                        }
                        temp[z] = '\0';
 
                        for (z = 0; z < l1; z++)
                        {
                            a[j][z] = a[i][z];
                            a[i][z] = '\0';
                        }
                        a[j][z] = '\0';
 
                        for (z = 0; z < strlen(temp); z++)
                        {
                            a[i][z] = temp[z];
                        }
                        break;
                    }    
                }
            }    
        }
 
    for (i = 0; i < l; i++)
    p[i] = '\0';
    k = 0;
    j = 0;
    for (i = 0; i < l; i++)
    {
        if (a[k][j] != '\0')
        {
            p[i] = a[k][j++];
        }
        else
        {
            k++;
            j = 0;
            p[i] = ' ';
        }
    }
    puts(p);        
}