1019

PAT_B_1019

#include<stdio.h>
#include<algorithm>
#include<string.h>
using namespace std;
int Isequ(int c)
{
    int num[10];
    int i = 1;
    while (i <= 4)
    {
        num[i] = c % 10;
        c = c / 10;
        i++;
    }
    if (num[1] == num[2] && num[2]== num[3] && num[3]== num[4])
        return 1;
    else
        return 0;
}
void Change(int *a, int *b, int ans)
{
    int num[10];
    int i = 1;
    while (i <= 4)
    {
        num[i] = ans % 10;
        ans = ans / 10;
        i++;
    }
    sort(num + 1, num + 5);
    i = 1;
    *a = *b = 0;
    while (i <= 4)
    {
        (*a) = (*a) * 10 + num[4-i+1];
        (*b) = (*b) * 10 + num[i];
        i++;
    }
}
void Solve(int c)
{
    int a, b, ans;
    ans = c;
    do
    {
        Change(&a, &b, ans);
        ans = a - b;
        printf("%04d - %04d = %04d\n", a, b, ans);
    } while (ans != 6174);
}
int main()
{
    int c;
    scanf("%d", &c);
    if (Isequ(c) == 1)
        printf("%04d - %04d = 0000\n", c, c);
    else
        Solve(c);
    system("pause");
    return 0;
}