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

#define ARRAY_SIZE 5

pthread_t THREAD_ID[5];

struct StructMax
{
    int ARRAY[ARRAY_SIZE];
    int LEFT;
    int RIGHT;
};



static int i = 0;
static int FLAG_FUNCTION_CALLS = 0;
static int FLAG_THREAD_ID = 0;

void *MAX_VALUE(struct StructMax *S_M)
{
    int ARRAY[ARRAY_SIZE];
    ARRAY = S_M->ARRAY;
    int *LEFT,*RIGHT;
    &LEFT = S_M->LEFT;
    &RIGHT = S_M->RIGHT;
    int MID;


    int ERR;
    FLAG_FUNCTION_CALLS++;

    int ACTIVE_THREAD_ID = pthread_self();


    if(&LEFT == &RIGHT)
    {
        if(FLAG_THREAD_ID <= 4)
        {
            printf("THREAD[%d] roger that and moving out...",ACTIVE_THREAD_ID);
            pthread_exit(&ARRAY[&LEFT]);
        }
        else
        {
            return (void *) ARRAY[S_M->LEFT];
        }

    }
    else
    {
        MID = (&LEFT + &RIGHT) / 2;
        void *U;
        if(FLAG_FUNCTION_CALLS <= 4)
        {
            FLAG_THREAD_ID++;
            ERR = pthread_create(&(THREAD_ID[FLAG_THREAD_ID]), NULL, &MAX_VALUE(S_M), NULL);
            if (ERR != 0)
                fprintf(stderr, "\nFAILED CREATE THREAD!");
            else
                printf("\n Thread created successfully\n");
            pthread_join(&THREAD_ID[FLAG_THREAD_ID],&U);
        }

        void *V;
        if(FLAG_FUNCTION_CALLS <= 4)
        {
            FLAG_THREAD_ID++;
            ERR = pthread_create(&(THREAD_ID[FLAG_THREAD_ID]), NULL, &MAX_VALUE(S_M), NULL);
            if (ERR != 0)
                fprintf(stderr, "\nFAILED CREATE THREAD!");
            else
                printf("\n Thread created successfully\n");
            pthread_join(&THREAD_ID[FLAG_THREAD_ID],&V);
        }

        if(FLAG_THREAD_ID <= 4)
        {
            printf("THREAD[%d] roger that and moving out...",ACTIVE_THREAD_ID);
            pthread_exit(U > V ? &U : &V);
        }
        else
        {
            return (U > V ? (void *)U : (void *)V);
        }
    }
}

int main()
{
    int N,i,ERR;
    void *MAXIMUM_VALUE;

    struct StructMax MY_STRUCT;

    int BUFFER[ARRAY_SIZE];
    printf("\nEnter Array values : \n");
    for(i = 0; i < N; i++)
        scanf("%d", &BUFFER[i]);

    int *LEFT, *RIGHT;
    MY_STRUCT->ARRAY = BUFFER;
    MY_STRUCT->LEFT = 0;
    MY_STRUCT->RIGHT = ARRAY_SIZE-1;

    ERR = pthread_create(&(THREAD_ID[0]), NULL, &MAX_VALUE(MY_STRUCT), NULL);
    if (ERR != 0)
        fprintf(stderr, "\nFAILED CREATE THREAD!");
    else
        printf("\n Thread created successfully\n");

    pthread_join(&THREAD_ID[4],&MAXIMUM_VALUE);
    printf("\n%d\nNumber of time the recursive function is called: %d", (int)MAXIMUM_VALUE,FLAG_FUNCTION_CALLS);

    return 0;
}