回文寻找

版权声明:本文为博主原创文章,未经博主允许不得转载。 https://blog.csdn.net/a_step_further/article/details/77074419

题目:寻找一个大于10的最小正整数,使其本身、二进制转化值、八进制转化值,都是回文


暴力解法:

#include <iostream>
#include <cstring>
#include <sstream>

using namespace std;


string conv(int N, int jinzhi);
template<class T> string to_string(const T& t);
int judgeHW(string input);

int main()
{
    int m = 11;
    int i;
    while(m > 10){
        i ++;
        string shijinzhi = to_string(m);
        string twojinzhi = conv(m,2);
        string eightjinzhi = conv(m,8);
        if(judgeHW(tenjinzhi) && judgeHW(twojinzhi) && judgeHW(eightjinzhi)){
            cout << "循环了 " << i << "次,找到 " << m << endl;
            cout << "3种进制下的数字分别为:" ;
            cout << tenjinzhi << " " << twojinzhi << " " << eightjinzhi << endl;
            break;
        }
        m ++;
    }
    return 0;
}

//将N转化为jinzhi进制
为string conv(int N, int jinzhi){
    string output;
    while(N > 0){
        int yushu = N % jinzhi;
        N = N/jinzhi;
        output = to_string(yushu) + output;
    }
    return output;
}

template<class T> string to_string(const T& t){
    ostringstream os;
    os << t;
    return os.str();
}

int judgeHW(string input){
    int flag = 1;
    int i = 0;
    int j = input.length() - 1;
    while(i <= j){
        if(input[i] == input[j]){
            i += 1;
            j -= 1;
            continue;
        }else{
            flag = 0;
            break;
        }
    }
    return flag;
}

多动一下脑,如果一个数字转化为二进制以后是回文,那么个位数一定是1,因为如果是0则要求首位也是0,不合理。故而该数一定是一个奇数。那么在上述循环遍历时,只判断奇数即可。

猜你喜欢

转载自blog.csdn.net/a_step_further/article/details/77074419