84 lines
1.4 KiB
C
84 lines
1.4 KiB
C
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#include <stdio.h>
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#include <stdlib.h>
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#define MAX_SIZE 100
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typedef struct {
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int items[MAX_SIZE];
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int top;
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} Stack;
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Stack* createStack() {
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Stack* s = (Stack*)malloc(sizeof(Stack));
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s->top = -1;
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return s;
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}
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void push(Stack* s, int x) {
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if (s->top == MAX_SIZE - 1) {
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printf("Stack Overflow\n");
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return;
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}
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s->items[++(s->top)] = x;
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}
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int pop(Stack* s) {
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if (s->top == -1) {
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printf("Stack Underflow\n");
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return -1;
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}
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return s->items[(s->top)--];
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}
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int isEmpty(Stack* s) {
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return s->top == -1;
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}
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typedef struct {
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Stack* s1;
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Stack* s2;
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} Queue;
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Queue* createQueue() {
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Queue* q = (Queue*)malloc(sizeof(Queue));
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q->s1 = createStack();
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q->s2 = createStack();
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return q;
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}
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void enqueue(Queue* q, int x) {
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push(q->s1, x);
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}
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int dequeue(Queue* q) {
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int x;
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if (isEmpty(q->s1) && isEmpty(q->s2)) {
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printf("Queue is empty\n");
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return -1;
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}
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if (isEmpty(q->s2)) {
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while (!isEmpty(q->s1)) {
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x = pop(q->s1);
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push(q->s2, x);
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}
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}
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return pop(q->s2);
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}
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int main() {
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Queue* q = createQueue();
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enqueue(q, 1);
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enqueue(q, 2);
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enqueue(q, 3);
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printf("%d\n", dequeue(q));
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printf("%d\n", dequeue(q));
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enqueue(q, 4);
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printf("%d\n", dequeue(q));
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printf("%d\n", dequeue(q));
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return 0;
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}
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