CCF-Markdown-201703-3

这道题不存在递归结构

   比如区块之间的相互嵌套 还有"[ [] ]" 链接的相互嵌套, 所以直接处理就好了

还可以

#include <bits/stdc++.h>
using namespace std;
string trans (string str) {
    string tmp; int i=0;
    while (i<str.size()) {
        bool flag=0; string txt,link;
        while (i<str.size()&&str[i]!='[')  tmp+=str[i++];
        if (str[i]=='[') { flag=1; i++;}
        if (flag) {
            while (str[i]!=']') txt+=str[i++];
            i+=2;
            while (str[i]!=')') link+=str[i++];
            i++;
            tmp+="<a href=""+link+"">"+txt+"</a>";
        }
    }
    str=tmp; tmp=""; i=0;
    while (i<str.size()) {
        bool flag=0; string txt;
        while (i<str.size()&&str[i]!='_') tmp+=str[i++];
        if (str[i]=='_') {flag=1; i++;}
        if (flag) {
            while (str[i]!='_') txt+=str[i++];
            i++;
            tmp+="<em>"+txt+"</em>";
        }
    }
    return tmp;
}
void trs2(string str) {
    int i=1; for (;str[i]==' ';i++);
    cout<<"<li>"<<trans(str.substr(i))<<"</li>
";
}
int main ()
{
    string str;
    //freopen("test.txt","r",stdin);
    while (getline(cin,str)) {
        if (str[0]=='#') {
            int i=0,x=0;
            for (;str[i]=='#';i++) x++;
            for (;str[i]==' ';i++);
            cout<<"<h"<<x<<">"<<trans(str.substr(i))<<"</h"<<x<<">
";
        }
        else if (str[0]=='*') {
            cout<<"<ul>
";
            trs2(str);
            while (getline(cin,str)&&str.size()!=0) 
                trs2(str);
            cout<<"</ul>
";
        }
        else if (str.size()!=0) {
            cout<<"<p>"<<trans(str);
            while (getline(cin,str)&&str.size()!=0)
                cout<<"
"<<trans(str);
            cout<<"</p>
";
        }
    }
    return 0;
}