Here's one way.
Code:
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
//alpha - character array stores the eniter alphabet
char *Alpha = "abcdefghijklmnopqrstuvwxyz";
int main(void)
{
char *original = "abc32fe5v";
char Out[80] = "";
size_t alpha_count;
char *p;
p = original;
while (*p != '\0')
{
alpha_count = strspn(p,Alpha);
printf("alpha_count:%d\n",alpha_count);
strncat(Out,p,alpha_count);
p += alpha_count;
printf("p:%s\n",p);
p += strcspn(p,Alpha);
printf("p:%s\n",p);
getchar();
}
printf("Out:%s\n",Out);
return 0;
}