1...#include <stdio.h>
#include <string.h>
#include <ctype.h>
int main() {
    int n;
    if (scanf("%d", &n) != 1 || n < 1 || n > 1000) {
        printf("Invalid input\n");
        return 0;
    }
    
    char names[n][101];
    
    for (int i = 0; i < n; i++) {
        scanf("%s", names[i]);
        for (int j = 0; j < strlen(names[i]); j++) {
            if (!isalnum(names[i][j])) {
                printf("Invalid input\n");
                return 0;
            }
        }
    }
    for (int i = 0; i < n; i++) {
        printf("%s", names[i]);
        if (i < n - 1) printf(" ");
    }
    printf("\n");
    
    return 0;
}