多项式 Wannafly挑战赛22

后缀表达式大整数(加法、乘法、gcd java)
  1 import java.math.BigInteger;
  2 import java.util.Scanner;
  3  
  4 class Work {
  5     String str;
  6     int _num,_sym;
  7     int []sym=new int[1000];
  8     BigInteger []num=new BigInteger[1000];
  9     int []w=new int[1000];
 10      
 11     Work() {
 12         BigInteger x,y;
 13         int wx,wy;
 14         Scanner in=new Scanner(System.in);
 15         str=in.nextLine();
 16         work();
 17         x=num[1];
 18         wx=w[1];
 19         str=in.nextLine();
 20         work();
 21         y=num[1];
 22         wy=w[1];
 23          
 24         if (wx>wy)
 25             System.out.println("1/0");
 26         else if (wx<wy)
 27             System.out.println("0/1");
 28         else
 29         {
 30             BigInteger z;
 31             z=x.gcd(y);
 32             x=x.divide(z);
 33             y=y.divide(z);
 34             System.out.print(x+"/"+y);
 35         }
 36         in.close();
 37     }
 38      
 39     void cal()
 40     {
 41         if (sym[_sym]==2)
 42         {
 43             if (w[_num-1]<w[_num])
 44             {
 45                 w[_num-1]=w[_num];
 46                 num[_num-1]=num[_num];
 47             }
 48             else if (w[_num-1]==w[_num])
 49                 num[_num-1]=num[_num-1].add(num[_num]);
 50         }
 51         else if (sym[_sym]==3)
 52         {
 53             w[_num-1]+=w[_num];
 54             num[_num-1]=num[_num-1].multiply(num[_num]);
 55         }
 56         _sym--;
 57         _num--;
 58     }
 59      
 60     void work()
 61     {
 62         int len,i;
 63         BigInteger z;
 64         len=str.length();
 65         z=BigInteger.valueOf(1);
 66         _num=0;
 67         _sym=0;
 68         sym[0]=0;
 69       
 70         for (i=0;i<len;i++)
 71         {
 72             if (str.charAt(i)=='x')
 73             {
 74                 num[++_num]=z;
 75                 w[_num]=1;
 76             }
 77             else
 78             {
 79                 switch(str.charAt(i))
 80                 {
 81                     case '+':
 82                         while (sym[_sym]>=2)
 83                             cal();
 84                         sym[++_sym]=2;
 85                         break;
 86                     case '*':
 87                         while (sym[_sym]>=3)
 88                             cal();
 89                         sym[++_sym]=3;
 90                         break;
 91                     case '(':
 92                         sym[++_sym]=1;
 93                         break;
 94                     case ')':
 95                         while (sym[_sym]!=1)
 96                             cal();
 97                         _sym--;
 98                         break;
 99                 }
100             }
101         }
102         while (_sym>0)
103             cal();
104     }
105 }
106  
107 public class Main {
108     public static void main(String[] args) {
109         Work work=new Work();
110     }
111 }