To me, when doing C/C++:
0 would digit zero, that is, a numerical value.
'0' could be the character capital oh or the character zero. For example:
char word[10] = "Oxford";
char number[10] = "01234";
Depending on typeface used 'O' may look exactly like '0' making it difficult to tell them apart out of context.
'/0' is the null character used to terminate strings in C/C++. 这里是用转义字符的八进制表示的'/ddd'
'/0' = 0 =0x00=000= '/x00'='/000' = NULL
"/0" is an empty string. strlen("/0" ) = 0 "/0" 是空字符串，并不包任何字符，因为字符串就是以null character '/0'作为结束的
16进制常整数 0x开头 如：0xff
8进制常整数 0开头 如：0ff
printf("%sb/n","/0");
printf("%d/n",strlen("/0"));
