POJ1555-Polynomial Showdown

http://poj.org/problem?id=1555

我再也不想写if-else了。。。。。

#include<stdio.h>
int main(void)
{
    int i,low,high,flag,num[9];
    while(scanf("%d%d%d%d%d%d%d%d%d",&num[8],&num[7],&num[6],&num[5],&num[4],&num[3],&num[2],&num[1],&num[0])!=EOF)
    {
        flag=1;
        low=0;  
        while(num[low]==0&&low<9) 
           low++;
        high=8; 
        while(num[high]==0&&high>=0) 
           high--;
        if(low>high) 
        {
            printf("0\n"); 
            continue;
        }
        for(i=high;i>=low;i--)
        {
            if(num[i]!=0)
            {
                if(flag==1)
                {
                    flag=0;
                    if(i==0) 
                       printf("%d",num[i]);
                    else if(i==1)
                    {
                        if(num[i]==-1) 
                           printf("-x");
                        else if(num[i]==1)
                           printf("x");
                        else 
                           printf("%dx",num[i]);
                    }
                    else 
                    {
                        if(num[i]==-1) 
                           printf("-x^%d",i);
                        else if(num[i]==1)
                           printf("x^%d",i);
                        else 
                           printf("%dx^%d",num[i],i);
                    }
                 }
                 else
                   {
                        if(num[i]>0)
                    {
                        if(num[i]==1)
                        {
                            if(i==0) 
                               printf(" + 1");
                            else if(i==1) 
                               printf(" + x");
                            else 
                               printf(" + x^%d",i);
                        }
                        else
                        {
                            if(i==0) 
                               printf(" + %d",num[i]);
                            else if(i==1)
                               printf(" + %dx",num[i]);
                            else 
                               printf(" + %dx^%d",num[i],i);
                        }
                    }
                    else 
                    {
                        if(num[i]==-1)
                        {
                            if(i==0) 
                               printf(" - 1");
                            else if(i==1) 
                               printf(" - x^");
                            else 
                               printf(" - x^%d",i);
                        }
                        else
                        {
                            if(i==0) 
                               printf(" - %d",0-num[i]);
                            else if(i==1)
                               printf(" - %dx",0-num[i]);
                            else 
                               printf(" - %dx^%d",0-num[i],i);
                        }
                    }
                }
            }
        }
        printf("\n");
    }
    return 0;
}