例6-5
#include<stdio.h> int main(void) { char ch;
printf("input characters:"); ch=getchar(); while(ch!='\n'){ if(ch>='A'&&ch<='Z') ch=ch-'A'+'a'; else if(ch>='a'&&ch<='z') ch=ch-'a'+'A'; putchar(ch); ch=getchar(); } return 0; }
#include<stdio.h> int main(void) { char ch;
printf("input characters:"); ch=getchar(); while(ch!='\n'){ if(ch>='A'&&ch<='Z') ch=ch-'A'+'a'; else if(ch>='a'&&ch<='z') ch=ch-'a'+'A'; putchar(ch); ch=getchar(); } return 0; }
