C/ctype.h/isalpha
int isalpha(int ch)
<source lang="cpp">
//Declaration: int isalpha(int ch); //Return: returns nonzero if ch is a letter or zero if not.
#include <ctype.h> #include <stdio.h> int main(void) { char ch; for(;;) { ch = getchar(); if(ch == ".") { break; } if(isalpha(ch)) { printf("%c is a letter\n", ch); } } return 0; }
/* a a is a letter a a is a letter d d is a letter .
- /
</source>