return (ch>='0' && ch

CH3-CH=CH-CH=CH-CH3是否存在? main() { char ch; ch='H'-'A'+'0'; printf("%c\n",ch); } ch是字符型变量,判断ch=‘a+b';ch='\0';ch='7'+'9';ch=5+9;哪个对? CH3-CH=CH-C≡CH 如何命名? CH2=CH-CH=CH2 CH3CH=CH-CH=CH2 + Br2? CH3-CH=CH-CH3命名 CH2=CH-CH(CH3)-CH2OH是什么? 关于有机物HOOC-CH=CH-CH2OH HOOC-CH=CH-CH2OH是什么 char a=0,ch; while((ch=getchar())!='\n') { if(a%2!=0&&(ch>=' union pw {int i;char ch[2]; }a; main () {a.ch[0]=10; a.ch[1]