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

int readLine(char text[], size_t capacity) {
    if (fgets(text, (int)capacity, stdin) == NULL) return 0;
    size_t length = strlen(text);
    if (length > 0 && text[length - 1] == '\n') text[--length] = '\0';
    else if (!feof(stdin)) {
        int ch = getchar();
        if (ch != '\n' && ch != EOF) return 0;
    }
    if (length > 0 && text[length - 1] == '\r') text[length - 1] = '\0';
    return 1;
}

int main(void) {
    char text[256];
    if (!readLine(text, sizeof text) || text[0] == '\0') {
        puts("Invalid input."); return 1;
    }
    size_t left = 0, right = strlen(text);
    int palindrome = 1;
    while (left < right) {
        --right;
        if (text[left] != text[right]) { palindrome = 0; break; }
        ++left;
    }
    printf("Palindrome: %s\n", palindrome ? "yes" : "no");
    return 0;
}