16进制转化8进制---map

#include "stdio.h"
#include "string.h"
#include "string"
#include "iostream"
#include "math.h"
#include "map"
#include "queue"
#include "malloc.h"
using namespace std;
map<char,string> mp;

int main()
{
    mp['']="";mp['']="";mp['']="";mp['']="";mp['']="";
    mp['']="";mp['']="";mp['']="";mp['']="";mp['']="";
    mp['A']="";mp['B']="";mp['C']="";mp['D']="";mp['E']="";
    mp['F']="";
    int a;
    char test[];
    cin >> a;
    while(a--)
    {

        memset(test,,sizeof(test));
        string b="";
        cin>>test;
        for(int i = ;i < strlen(test);i++)
        {
            b += mp[test[i]];
        }
        int len = b.length();
        if(len%==)
            b = "" + b;
        else if(len%==)
            b = "" + b;
        int flag = ;
        for(int i =  ;i < b.length(); i = i + )
        {
            int num = *(b[i]-'')+*(b[i+]-'')+(b[i+]-'');
            if(num)
                flag = ;
            if(flag)
                cout<<num;

        }
        cout<<endl;
    }
    return ;
}

但是这个跑在蓝桥杯的题目中会超时，因为map查询是对数时间复杂度放在循环中会超时

更改map后通过

#include "stdio.h"
#include "string.h"
#include "string"
#include "iostream"
#include "math.h"
#include "map"
#include "queue"
using namespace std;
map<char,string> mp;

int main()
{
    int a;
    string test;
    cin >> a;
    while(a--)
    {
        string b="";
        cin>>test;
        for(int i=;i<test.length();i++)//遍历，字符串上加上每一位
        {
            switch(test[i])
            {
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case '':b+="";break;
                case 'A':b+="";break;
                case 'B':b+="";break;
                case 'C':b+="";break;
                case 'D':b+="";break;
                case 'E':b+="";break;
                case 'F':b+="";break;
                default:break;
            }
        }
        int len = b.length();
        if(len%==)
            b = "" + b;
        else if(len%==)
            b = "" + b;
        int flag = ;
        for(int i =  ;i < b.length(); i = i + )
        {
            int num = *(b[i]-'')+*(b[i+]-'')+(b[i+]-'');
            if(num)
                flag = ;
            if(flag)
                cout<<num;
        }
        cout<<endl;
    }

    return ;
}