dejavu.c

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

char* check_uniqueness(const char *chars);

int main() {
    char chars[100] = "";
    char buffer[100] = "";

    scanf("%s", chars);

    printf("%s", check_uniqueness(chars));

    return 0;
}

char* check_uniqueness(const char *chars) {
    for (int i = 0; i < strlen(chars); i++) {
      if (strchr(&chars[i+1], chars[i])) {
        return "Deja Vu";
      }
    }
    return "Unique";
}