#include<stdio.h>
int *del_digit1( char *st1, char *st2 )
{
	char *temp = st1;
		while(*st1 != '\0')
		{
			if(isalpha(*st1))
			*st2=*st1;
			*st1++;
			*st2++;
                        else
                        *st1++;
	}
	*st2=*st1;
	return (temp);
}

int main(void)
{
	char st1[100];
	char st2[100];
	
	printf("input string\n");
	scanf("%s",st1);
	
	del_digit1(st1,st2);

	printf("%s\n",st2);

}

In function 'del_digit1':
Line 11: error: expected expression before 'else'
Line 15: warning: return from incompatible pointer type