基础练习 十六进制转八进制

#include <iostream>
#include<cstdio> 
#include<algorithm>
#include <string>
using namespace std;

char s[100010];

void conversion(char s[])
{
    string temp;
    int t;
    for (int i=0; s[i]!='\0'; i++)
    {
        if (s[i] <= '9' && s[i] >= '0') 
	    t = s[i] - '0'; 
	else 
	    t = s[i] - 'A' + 10;
        string tem;
        while(t)                           //十六进制转二进制
        {
            tem += ((t & 1) + '0');
            t >>= 1;
        }
        if(!tem.length())
            tem = "0000";
        while(tem.length() < 4) 
	    tem += '0';
        reverse(tem.begin(), tem.end());
        temp += tem;
    }
    int i = 0;
    int len = temp.length();
    while(temp.length() % 3!=0)
    {
    	temp = '0' + temp;
    	len++;
    }
    string cur;
    while(i < len)
    {
        cur += temp[i];
        if(cur.length() == 3)
        {
            int kk = 0;
            for(int j = 0; j < 3; j++)
        	kk = kk * 2 + cur[j] - '0';
            cur.clear();
            if(kk == 0 && i == 2);               //八进制前导零不输出 
	    else
		cout << kk;	
        }
        i++;
    }
    cout << endl;
}
int main()
{
    int n;
    scanf("%d", &n);
    while(n--)
    {
	scanf("%s", s);
	conversion(s);
    }
    return 0;
}