1 #include <iostream> 2 #include <cstdio> 3 #include <cstring> 4 using namespace std; 5 struct Set { 6     bool mark[128]; 7     Set() { 8         memset(mark, 0, sizeof(mark)); 9     }10     bool &operator [] (int x) {11         return mark[x];12     }13     void inp() {14         printf("input element: ");15         char str[102];16         cin>> str;17         for(int i = 0; str[i]; i++) {18             if(str[i] == ‘$‘) break;19             mark[str[i]] = 1;20         }21     }22     void outp(char str[]) {23         cout<< str;24         for(char i = 0; i < 128 && i >= 0; i++) {25             if(mark[i]) cout<< i<< " ";26         }27         cout<< endl;28     }29     void intersectionSet(Set A, Set B) {30         for(int i = 0; i < 128; i++) {31             (*this)[i] = A[i] && B[i];32         }33     }34     void unionSet(Set A, Set B) {35         for(int i = 0; i < 128; i++) {36             (*this)[i] = A[i] || B[i];37         }38     }39 };40 int main()41 {42     while(1) {43         Set A, B, C, D;44         A.inp();45         B.inp();46         C.intersectionSet(A, B);47         D.unionSet(A, B);48         A.outp("A: ");49         B.outp("B: ");50         C.outp("A ^ B: ");51         D.outp("A v B: ");52     }53     return 0;54 }