C Sort String Characters

#include <stdio.h>
#include <ctype.h>
#include <string.h>
int main()
{
int i, j, len, k = 0, len1;
char text[30], store[30];
printf("Enter a String : ");
gets(text);
len = strlen(text);
printf("Sorted Characters alphabetically : ");
for(i = 65;i <= 90;i++)
{
for(j = 0;j < len;j++)
{
if(text[j] == toupper(i) || text[j] == tolower(i))
{
store[k] = text[j];
k++;
}
}
}
len1 = strlen(store);
for(i = 0;i <= len1;i++)
printf("%c", store[i]);
return 0;
}