求两个集合的交集、差集和并集

#include <stdio.h>
#include <stdlib.h>

typedef struct node{
char data;
struct node * next;
}Linklist;

//尾插入法
Linklist * createLinklist2(){
char x;
Linklist * head,* p,* q;
head = (Linklist *)malloc(sizeof(Linklist));
head->next = NULL;
q = head;
printf("please input the values of the list!\n");
scanf("%c",&x);
while(x != '\n'){
p = (Linklist *)malloc(sizeof(Linklist));
p->data = x;
p->next = NULL;
q->next = p;
q = p;
scanf("%c",&x);
}
return head;
}

//打印
void print(Linklist * head){
Linklist * p;
p = head->next;
while(p != NULL){
printf("%2c",p->data);
p = p->next;
}
printf("\n");
}

int main(){
Linklist * La;
Linklist * Lb;
Linklist * Lc;      //Lc链表中保存的是集合A和集合B的交集
Linklist * Ld;      //Ld链表中保存的是集合A和集合B的差集
Linklist * Le;      //Le链表中保存的是集合A和集合B的并集

Linklist * pa,* pb,* pd;

Linklist * p,* q;
int flag1;
int flag2;

printf("create La!\n");
La = createLinklist2();
printf("\nLa:\n");
print(La);

printf("\n");

printf("create Lb!\n");
Lb = createLinklist2();
printf("\nLb:\n");
print(Lb);

//集合A和集合B的交集
Lc = (Linklist *)malloc(sizeof(Linklist));
Lc->next = NULL;
q = Lc;
pa = La->next;
while(pa){
pb = Lb->next;
flag1 = 0;
while(pb){
if(pa->data == pb->data){
flag1 = 1;
break;
}else{
pb = pb->next;
}
}
if(flag1 == 1){
p = (Linklist *)malloc(sizeof(Linklist));
p->data = pa->data;
p->next = q->next;
q->next = p;
q = p;
}
pa = pa->next;
}

printf("A集合和B集合的交集是：");
print(Lc);

//集合A和集合B的差集
Ld = (Linklist *)malloc(sizeof(Linklist));
Ld->next = NULL;
q = Ld;
pa = La->next;

while(pa){
pb = Lb->next;
flag2 = 0;
while(pb){
if(pa->data == pb->data){
flag2 = 1;
break;
}
pb = pb->next;
}
if(flag2 == 0){
p = (Linklist *)malloc(sizeof(Linklist));
p->data = pa->data;
p->next = q->next;
q->next = p;
q = p;
}
pa = pa->next;
}

printf("A集合和B集合的差集是：");
print(Ld);

//集合A和集合B的并集(AUB = (A-B)UB)
Le = (Linklist *)malloc(sizeof(Linklist));
Le->next = NULL;
q = Le;
pb = Lb->next;
pd = Ld->next;

while(pb){
p = (Linklist *)malloc(sizeof(Linklist));
p->data = pb->data;
p->next = q->next;
q->next = p;
q = p;
pb = pb->next;
}

while(pd){
p = (Linklist *)malloc(sizeof(Linklist));
p->data = pd->data;
p->next = q->next;
q->next = p;
q = p;
pd = pd->next;
}

printf("A集合和B集合的并集是：");
print(Le);

return 0;
}