A hard puzzle

  1 #include <stdio.h>
  2 
  3 int main(){
  4     int a;
  5     int b;
  6     int number;
  7     char two[5]="2486";
  8     char three[5]="3971";
  9     char four[3]="46";
 10     char seven[5]="7931";
 11     char eight[5]="8426";
 12     char nine[3]="91";
 13 
 14     while(scanf("%d%d",&a,&b)!=EOF){
 15         number=a%10;
 16 
 17         if(number==0){
 18             printf("0\n");
 19             continue;
 20         }
 21 
 22         if(number==1){
 23             printf("1\n");
 24             continue;
 25         }
 26 
 27         if(number==2){
 28             b%=4;
 29 
 30             if(b==0)
 31                 b=4;
 32 
 33             printf("%c\n",two[b-1]);
 34             continue;
 35         }
 36 
 37         if(number==3){
 38             b%=4;
 39 
 40             if(b==0)
 41                 b=4;
 42 
 43             printf("%c\n",three[b-1]);
 44             continue;
 45         }
 46 
 47         if(number==4){
 48             b%=2;
 49 
 50             if(b==0)
 51                 b=2;
 52 
 53             printf("%c\n",four[b-1]);
 54             continue;
 55         }
 56 
 57         if(number==5){
 58             printf("5\n");
 59             continue;
 60         }
 61 
 62         if(number==6){
 63             printf("6\n");
 64             continue;
 65         }
 66 
 67         if(number==7){
 68             b%=4;
 69 
 70             if(b==0)
 71                 b=4;
 72 
 73             printf("%c\n",seven[b-1]);
 74             continue;
 75         }
 76 
 77         if(number==8){
 78             b%=4;
 79 
 80             if(b==0)
 81                 b=4;
 82 
 83             printf("%c\n",eight[b-1]);
 84             continue;
 85         }
 86 
 87         if(number==9){
 88             b%=2;
 89 
 90             if(b==0)
 91                 b=2;
 92 
 93             printf("%c\n",nine[b-1]);
 94             continue;
 95 
 96         }
 97 
 98     }
 99     
100     return 0;
101 }