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

unsigned long int fib(unsigned long int n) {
    if (n <= 1) return n;
    return fib(n - 1) + fib(n - 2);
}

int main() {
    char buffer[1024];  // Buffer to store input data

    ssize_t bytes_read = read(0, buffer, sizeof(buffer) - 1);
    if (bytes_read < 0) {
        perror("Error reading input");
        return 1;
    }
    buffer[bytes_read] = '\0';  // Null-terminate the string

    // Parse the expected data length from the first 4 bytes for the first number
    if (bytes_read < 4) {
        fprintf(stderr, "Input is too short to contain valid data length.\n");
        return 1;
    }

    // First number length and number
    uint32_t first_num_length;
    memcpy(&first_num_length, buffer, sizeof(uint32_t));
    char *first_num_start = buffer + 4;
    if (bytes_read < 4 + first_num_length + 4) {  // Check if there is enough data for the first number and the second length
        fprintf(stderr, "Input does not contain enough data for the first number and the second length.\n");
        return 1;
    }

    // Second number length and number
    uint32_t second_num_length;
    memcpy(&second_num_length, first_num_start + first_num_length, sizeof(uint32_t));
    char *second_num_start = first_num_start + first_num_length + 4;
    if (bytes_read < 4 + first_num_length + 4 + second_num_length) {  // Check if there is enough data for the second number
        fprintf(stderr, "Input does not contain enough data for the second number.\n");
        return 1;
    }

    // Read and calculate Fibonacci numbers
    unsigned long int num1, num2;
    if (sscanf(first_num_start, "%lu", &num1) != 1 || sscanf(second_num_start, "%lu", &num2) != 1) {
        fprintf(stderr, "Failed to parse the numbers correctly.\n");
        return 1;
    }

    unsigned long int fib1 = fib(num1);
    unsigned long int fib2 = fib(num2);
    unsigned long int sum = fib1 + fib2;

    // Prepare output string
    char output[1024];
    int len = snprintf(output, sizeof(output), "Fibonacci(%lu) + Fibonacci(%lu) = %lu + %lu = %lu\n", num1, num2, fib1, fib2, sum);

    // Write to stdout
    write(1, output, len);

    return 0;
}