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

#define LINE_SIZE 128

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

struct node* push(struct node* head, char *data) {
    struct node* tmp;
    if ((tmp = (struct node*)malloc(sizeof(struct node))) == NULL) {
        printf("memory error\n");
        exit(-1);
    }
    tmp->data = data;
    tmp->next = head; //head = NULL -> tmp->next=NULL
    head = tmp;
    return head;
}

void display(struct node* head) {
    struct node* p;

    while (head != NULL) {
        p = head;
        printf("%s\n", head->data);
        head = head->next;
        free(p->data);
        free(p);
    }
}

int main() {
    struct node* head = NULL;
    char c;
    char *str;
    char buf[LINE_SIZE];
    int i = 0;
    while ((c = getchar()) != EOF) {
        if ((c <= 'Z' && c >= 'A') || (c <= 'z' && c >= 'a')) {
            buf[i] = c;
            i++;
        }
        if (c == '\n' || c == ' ' || c == '\t') {
            buf[i] = '\0';
            if ((str = (char *)malloc(i + 1)) == NULL) {
                printf("memory error");
                exit(-1);
            }
            strcpy(str, buf);
            head = push(head, str);
            i = 0;
        }
    }
    display(head);
}