USACO Palindromic Squares 【STL__string_的应用】

这里有个讲解 string 用法非常详细的博文：https://www.byvoid.com/zhs/blog/cpp-string

题目意思很简单啦，就是找回文

 

使用string可以高速Ａ过

 

Source code:

/*

ID: wushuai2

PROG: palsquare

LANG: C++

*/

//#pragma comment(linker, "/STACK:16777216") //for c++ Compiler

#include <stdio.h>

#include <iostream>

#include <fstream>

#include <cstring>

#include <cmath>

#include <stack>

#include <map>

#include <queue>

#include <vector>

#include <algorithm>

#define ll long long

#define Max(a,b) (((a) > (b)) ? (a) : (b))

#define Min(a,b) (((a) < (b)) ? (a) : (b))

#define Abs(x) (((x) > 0) ? (x) : (-(x)))



using namespace std;

const int INF = 0x3f3f3f3f;



string solve(int base, int n){

    string ss;

    while(n){

        if(n % base > 9){

            ss.push_back(n % base - 10 + 'A');

        } else{

            ss.push_back(n % base + '0');

        }

        n /= base;

    }

    reverse(ss.begin(), ss.end());

    return ss;

}



bool judge(string ss){

    string pp = ss;

    reverse(ss.begin(), ss.end());

    if(ss.compare(pp) == 0){

        return true;

    }

    return false;

}



int main() {

    ofstream fout ("palsquare.out");

    ifstream fin ("palsquare.in");

    int base;

    fin >> base;

    for(int i = 1; i <= 300; ++i){

        if(judge(solve(base, i * i))){

            fout << solve(base, i) << ' ' << solve(base, i * i) << endl;

        }



    }



    return 0;

}