cdemo/Kaprekar black hole.cpp

// 包含两种I/O库，可以使用任一种输入输出方式
#include <stdio.h>
#include <iostream>
using namespace std;

int small(int n)
{
    // n-输入的数，m-重排后的数
    int  m;
    if (n<10){
        m = n;
    }else if(n<100){
        m = n;
    }else{
        int a ,b, c;

        a = n/100;
        b = (n-a*100)/10;
        c = n%10;
        if (a > b) swap(a, b);
        if (a > c) swap(a, c);
        if (b > c) swap(b, c);
        m = a*100+b*10+c;
    }
    return m;
}

int big(int n)
{
    // n-输入的数，m-重排后的数
    int  m;
    int a ,b, c;
    if (n<10){
        m = 100*n;
    }else if(n<100){
        n = 10*n;
        a = n/100;
        b = (n-a*100)/10;
        c = n%10;
        if (a > b) swap(a, b);
        if (a > c) swap(a, c);
        if (b > c) swap(b, c);
        m = a*100+b*10+c;
    }else{
        a = n/100;
        b = (n-a*100)/10;
        c = n%10;
        if (a > b) swap(a, b);
        if (a > c) swap(a, c);
        if (b > c) swap(b, c);
        m = a*100+b*10+c;
    }
    return m;
}

int main()
{
    int n;
    int k=0;
    int kk=1;
    cin >> n;
    // 请在此添加代码，输出整数进入黑洞过程
    /********** Begin *********/
    while (k!=495){
        k = big(n)-small(n);
        cout<<kk<<':';
        cout << big(n) <<'-'<<small(n)<<'='<<k<<endl;
        n = k;
        kk ++;
    }
    /********** End **********/
    return 0;
}