单项选择题
A) x=4,y=4,a=1 B) x=5,y=5,a=1 C) x=5,y=4,a=3 D) x=5,y=4,a=1
A) gets(s); B) white((s[i++]=getchar())!='\n');s[i]=\0; C) scanf("%s",s); D) d0scanf("%c",&s[i]);while(s[i++]!='\n';s[i]='\0';