C和指针5.9.1

/*大写输入转为小写输出*/#include <stdio.h>#include <stdlib.h>//#include <ctype.h>int main(){    int c;    c=0;    while( ( c = getchar() ) != EOF )    {        //第一种        //putchar( tolower( c ) );        //第二种        if( c < 'Z' && c > 'A')        {            c += ('a'-'A');        }        putchar( c );       // printf("%c",c);    }    return 0;}