/* Bai tap 9_1 - Dem so lan xuat hien cac ky tu trong chuoi */

#include <stdio.h>

#include <ctype.h>

int main()

{

char chuoi[80];

int i = 0, count = 0;

printf("

Nhap vao mot chuoi bat ky : ");

gets(chuoi);

while (chuoi[i] != 0)

{

if (isalpha(chuoi[i++]))

count++;

}

printf("So ky tu trong chuoi = %d", count);

getch();

}