PAT1019数字黑洞 (20)

#include<iostream>
#include<algorithm>
using namespace std;

int  input,n1,n2;
int number1[4];

int processLess(int input)
{
for(int i=0;i<4;i++)
{
number1[i]=input%10;
input/=10;
}
sort(number1,number1+4);
int toreturn=0;
for(int i=0;i<4;i++)
{
toreturn=toreturn*10+number1[i];
}
return toreturn;
}

bool big(const int A,const int B)
{
return A>B;
}
int processBig(int input)
{
for(int i=0;i<4;i++)
{
number1[i]=input%10;
input/=10;
}
sort(number1,number1+4,big);
int toreturn=0;
for(int i=0;i<4;i++)
{
toreturn=toreturn*10+number1[i];
}
return toreturn;

}

int main()
{

cin>>input;

while(true)
{

n1=processBig(input);

cout.fill('0');
cout.width(4);
cout<<n1<<" - ";

n2=processLess(input);
cout.width(4);
cout<<n2<<" = ";
input=n1-n2;
cout.width(4);
cout<<input<<endl;
if(input==0||input==6174)
{
break;
}

}

}