NBUT [1369] A Breaking Computer

A Breaking Computer

题目： http://cdn.ac.nbutoj.com/Problem/view.xhtml?id=1369

参考了网上的代码才ac了，尝试了用string来做，但是TLE了，做了我n久的，桑心死了，基础很重要啊。

include <iostream>
#include <vector>
#include <stdio.h>
using namespace std;
#define MAXN 200000

char ht[MAXN+10];
vector <char> ans[MAXN+10];

int main()
{
    while(~scanf("%s",ht))
    {
        int i,r,kar;
        for(i=0;i<MAXN;i++)
            ans[i].clear();
        r = 0;
        kar = 0;
        for(i=0;ht[i]!='\0';i++)
        {
            if(ht[i]=='[')
            {
                r++;
                kar = r;
            }
            else if(ht[i]==']')
            {
                kar = 0;
            }
            else
            {
                ans[kar].push_back(ht[i]);
            }
        }
        for(i=r;i>=0;i--)
        {
            for(int j=0;j<ans[i].size();j++)
            {
                printf("%c",ans[i][j]);
            }
        }
        printf("\n");
    }
    return 0;
}

#include <iostream>
#include <vector>
#include <string>
#include <stdio.h>
using namespace std;
#define MAXN 200000

char ht[MAXN+10];

int main()
{
    string str1,str2,str3;
    while(~scanf("%s",ht))
    {
        str1 = ht;
        int a=0,b=0,c=0;
        a = str1.find('[',b);
        if(a==string::npos)
        {
            printf("%s\n",str1.c_str());
            continue;
        }
        while(a!=string::npos)
        {
            str2.append(str1,b,a-b);
            c = str1.find(']',b);
            if(c==string::npos) c = str1.length();
            str3.assign(str1,a+1,c-a-1);
            str2 = str3 + str2 ;
            b = c+1;
            a = str1.find('[',b);
        }
        if(c!=str1.length())
        {
            c = str1.length();
            str2.append(str1,b,c);
        }
        printf("%s\n",str2.c_str());
        str1.clear();
        str2.clear();
    }
    return 0;
}