hdu 1111 Secret Code

http://acm.hdu.edu.cn/showproblem.php?pid=1111

复数除法：

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

int a[110];
__int64 n;
int x1,y1,b1,b2;
int t1;
bool flag;

void dfs(int cnt)
{
    if(cnt>100) return;
    if(x1==0&&y1==0)
    {
        flag=true;
        t1=cnt;
        return;
    }
    for(int i=0; i*i<=n; i++)
    {
        if(flag) return;
        __int64  xx=(x1-i)*b1+y1*b2;
        __int64  yy=y1*b1-(x1-i)*b2;
        if(xx%n==0&&yy%n==0)
        {
            x1=xx/n;
            y1=yy/n;
            a[cnt]=i;
            dfs(cnt+1);
        }
    }
}

int main()
{
    int t;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d%d%d%d",&x1,&y1,&b1,&b2);
        n=b1*b1+b2*b2;
        flag=false;
        dfs(0);
        if(!flag)
        {
            printf("The code cannot be decrypted.
");
        }
        else
        {
            printf("%d",a[t1-1]);
            for(int i=t1-2; i>=0; i--)
            {
                printf(",%d",a[i]);
            }
            printf("
");
        }
    }
    return 0;
}