yxc yyds

我是菜狗呜呜呜呜，他的方法好妙

题目回文平方

#include <iostream>
#include <cstring>
#include <algorithm>
using namespace std;
int b;
int get(int x)
{
    if(x<=9)return x+'0';//转换此时的数就是倒取得到的进制数，余数是0到9表明是转为10进制以下
    return x+'A'-10;
}
string base(int a,int b)
{
    string x;
    while(a)x+=get(a%b),a/=b;
    reverse(x.begin(),x.end());
    return x;
}
bool check(string ans)
{
    for(int i=0,j=ans.size()-1;i<j;i++,j--)
    {
        if(ans[i]!=ans[j])
        return false;
    }
    return true;
}
int main()
{
    cin>>b;
    for(int i=1;i<=300;i++)
    {
        auto ans=base(i*i,b);
        if(check(ans))
         cout <<base(i,b)<<' '<<ans<<endl;
    }
    return 0;
}

进制转换的核心(拙见)

采用字符串拼接方式，以二进制为桥梁，进行转换；
细节：以十六转八为例，得到二进制的十六进制数之后，先倒序取出，因为可能存在需要补零的情况，补完零后再倒序取出才是正序的二进制数，之后通过substr(i,3)(第i个之后三位)判定，来变成八进制数，因为可能存在前导零的情况，可以继续用
substr(1,len-1)(抓去第一个到len-1为止

code

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

string get_two(string a) {
    //int j=0;
    string s1 = "";
    int len = a.size();
    for (int i = 0; i < len; i++ ) {
        switch (a[i]) {
            case '0':
                s1 += "0000";
                break;
            case '1':
                s1 += "0001";
                break;
            case '2':
                s1 += "0010";
                break;
            case '3':
                s1 += "0011";
                break;
            case '4':
                s1 += "0100";
                break;
            case '5':
                s1 += "0101";
                break;
            case '6':
                s1 += "0110";
                break;
            case '7':
                s1 += "0111";
                break;
            case '8':
                s1 += "1000";
                break;
            case '9':
                s1 += "1001";
                break;
            case 'A':
                s1 += "1010";
                break;
            case 'B':
                s1 += "1011";
                break;
            case 'C':
                s1 += "1100";
                break;
            case 'D':
                s1 += "1101";
                break;
            case 'E':
                s1 += "1110";
                break;
            case 'F':
                s1 += "1111";
                break;
        }
    }
    //cout << "1，s1:" << s1 ;
    return s1;
}

string get_eight(string s) {
    string s1 = "", s2 = "", s3 = "";
    for (int i = s.length() - 1; i >= 0; i--) { //逆序
        s1 += s[i];

    }
    //cout << "s1:" << s1 << endl;
    if (s1.length() % 3 != 0) {//补零
        for (int i = 0; i < (3 - (s.length() % 3)); i++) {
            s1 += "0";
        }
    }
    //cout << "s1:" << s1 << endl;
    for (int i = s1.length() - 1; i >= 0; i--) {
        s2 += s1[i];
    }
    //cout << "s2:" << s2 << endl;
    for (int i = 0; i < s2.length(); i += 3) {
        if (s2.substr(i, 3) == "000")
            s3 += "0";      //提取i之后的三个字符(包括k)
        else if (s2.substr(i, 3) == "001")
            s3 += "1";
        else if (s2.substr(i, 3) == "010")
            s3 += "2";
        else if (s2.substr(i, 3) == "011")
            s3 += "3";
        else if (s2.substr(i, 3) == "100")
            s3 += "4";
        else if (s2.substr(i, 3) == "101")
            s3 += "5";
        else if (s2.substr(i, 3) == "110")
            s3 += "6";
        else if (s2.substr(i, 3) == "111")
            s3 += "7";
    }
    if (s3.substr(0, 1) == "0") {
        s3 = s3.substr(1, s3.length() - 1);
    }
    //cout << "s3:" << s3 << endl;
    return s3;
}

int main() {
    int n;
    cin >> n;
    string two_n, eight_num;
    string a[n];
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }
    for (int i = 0; i < n; i++) {
        two_n = get_two(a[i]);
        eight_num = get_eight(two_n);
        //cout << two_n << endl;
        cout << eight_num << endl;
    }
    return 0;
}