[백준/C] 18258번 큐 2

https://www.acmicpc.net/problem/18258

18258번: 큐 2

정적 배열 큐

 

fscanf로 입력받은 후fgetc(stdin)으로 버퍼를 비워주었다

 

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MALLOC(p,s) {\
    if (!((p) = malloc(s))) {\
    	fprintf(stderr, "Insufficient memory.");\
        exit(EXIT_FAILURE);\
    }\
}
#define MAX_Q_SIZE 2000001
#define MAX(x,y) ((x) > (y)) ? (x):(y) 
int queue[MAX_Q_SIZE];
int front = 0;
int rear = -1;

int main(void) {
    int size;
    int n, data;
    char order[10];

    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
        scanf("%s", order);
        fgetc(stdin); // 버퍼 비우기
        
        size = rear - front + 1;
        if (!strcmp(order, "push")) {
            scanf("%d", &data);
            fgetc(stdin); // 버퍼 비우기
            queue[++rear] = data;
            
        }

        else if (!strcmp(order, "pop")) {
            if (size == 0) printf("-1\n");
            else {
                printf("%d\n", queue[front++]);
            }
           
        }

        else if (!strcmp(order, "size")) {
            printf("%d\n", size);
        }

        else if (!strcmp(order, "empty")) {
            if (size == 0) printf("1\n");
            else printf("0\n");
        }

        else if (!strcmp(order, "front")) {
            if (size == 0) printf("-1\n");
            else printf("%d\n", queue[front]);
        }

        else if (!strcmp(order, "back")) {
            if (size == 0) printf("-1\n");
            else printf("%d\n", queue[rear]);
        }
    }
    return 0;

}