#include <stdio.h>
main(){
    char s[2000];
    int i, n;

    printf("Input letters.\n");
    gets( s );/* 改行まで文字列の入力 */

    n = 0 ;
    i = 0 ;
    while( s[i] != 0 ){
       if( s[i]>='a' && s[i] <= 'z' ){
          n = n + 1 ;
      }
      i = i + 1 ;
    }
    printf("number of lower case letters in '%s' is %d\n", s, n);
}