POJ1350 Cabric Number Problem [模拟]

#include<iostream>
#include<string>
#include<algorithm>
#define max(a,b) (a>b?a:b)
#define abs(a) ((a)>0?(a):-(a))
#define min(a,b) (a<b?a:b)
using namespace std;
int n,m;
int arr[4];
int main()
{
while(scanf("%d",&n),n!=-1)
{
m=0;
printf("N=%d:\n",n);
while(n!=0&&n!=6174)
{
int a=0,b=0,i=0;
while(n)
{
arr[i++]=n%10;
n/=10;
}
sort(arr,arr+i);
for(int j=0;j<i;j++)
{
a*=10;
b*=10;
a+=arr[j];
b+=arr[i-1-j];
}
n=b-a;
m++;
if((n==0&&m==1)||(m==1&&i!=4))
{
m=0;
printf("No!!\n");
break;
}
printf("%d-%d=%d\n",b,a,n);
};
if(m>0)
printf("Ok!! %d times\n",m);
}
return 0;
}