C语言学习笔记（十二）
#include

#define STRMAXNUM 10000  /* 用于存储输出字符串 */

/* 练习1-23 编写一个删除C语言程序中所有注释语句。要正确处理带引号的字符串与字符常量。在C语言中，注释不允许 嵌套。*/
main() {
    int c, inNote, inStr, i, inChar;
    char outStr[STRMAXNUM];

    i = inNote = inStr = inChar = 0; /* 0表示还没有出现注释‘/’符号，1表示出现了‘/’，2表示出现了‘*’ , 3表示出现了右边* */
    while((c = getchar()) != EOF) {
        if (c == '\'' && inNote == 0 && inStr == 0) {
            outStr[i++] = c;
            if( inChar == 0) {
                inChar = 1;  /* 没匹配过，就开始匹配 */
            }  else if( outStr[i-2] == '\\' ) { /* 确定上一个字符不是转义字符 */
                if (outStr[i-3] == '\\')
                    inChar = 0; /* 匹配过，就结束匹配 */
            } else {
                inChar = 0;
            }
        }else if (c == '"' && inNote == 0 && inChar == 0) {/* 要匹配字符串，字符串不能在注释里 */
            outStr[i++] = c;
            if( inStr == 0) {
                inStr = 1;  /* 没匹配过，就开始匹配 */
            } else if( outStr[i-2] == '\\' ) { /* 确定上一个字符不是转义字符 */
                if (outStr[i-3] == '\\')
                    inStr = 0; /* 匹配过，就结束匹配 */
            } else {
                inStr = 0;
            }
        } else if (inChar == 1) {
            outStr[i++] = c; /* 在字符中*/
        } else if( inStr == 1) {
            outStr[i++] = c; /* 在字符串中*/
        } else if(inNote == 3) { /* 右边注释*已经出现，匹配/,如果匹配上就一次注释匹配完毕，没有匹配上,把状态置为左注释匹配完毕的状态  */
            if (c == '/') {
                inNote = 0;  /* 注释匹配完毕，重置注释标志 */
            } else {
                inNote = 2;
            }
        } else if (inNote == 2) { /* 在注释里*/
           if (c == '*') {
               inNote = 3;
           }
        } else {
             if (inNote == 0 && c == '/') {
                inNote = 1;
            } else if (inNote == 1 && c == '*') {
                inNote = 2;
            } else {
                if (inNote == 1)
                    outStr[i++] = '/';  /* 没匹配到注释，就输出/ */
                inNote = 0;
                outStr[i++] = c;
            }
        }
    }
    outStr[i] = '\0';
    printf("%s\n", outStr);
}