#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <sys/time.h>
#include <time.h>

#define MAX 2147483647
int vetorMin;

long long numElementos =    159999999;

int numThreads, interPorThread, max;
unsigned char *vetor, *maiores;
pthread_mutex_t mutex;

double MyClock() {
    struct timeval tv;
    gettimeofday(&tv, NULL);
    return (tv.tv_sec * 1000000) + tv.tv_usec;
}

void *min(void *arg){
    int t = (long)arg, i, ini, fim;
    ini = t*interPorThread;
    unsigned char meuMin;

    if((t == numThreads-1) && (numElementos%numThreads != 0))
        fim = numElementos;
    else
        fim = t*interPorThread + interPorThread;

    meuMin = vetor[ini];
    for(i = ini+1; i < fim; i++){
        if(meuMin <= vetor[i])
            meuMin = vetor[i];
    }
    maiores[t] = meuMin;
}

int main(int argc, char *argv[]){
    srand(0);
    //srand( (unsigned)time(NULL) );

    double inicio;
    int i;
    if (argc != 2) {
      fprintf(stderr, "usage: ./a.out <threads>\n");
      exit(1);
    }

    vetor = (unsigned char*)malloc(numElementos* sizeof(unsigned char));
    maiores = (unsigned char*)malloc(numThreads* sizeof(unsigned char));

    if(vetor != NULL){
        for(i = 0; i < numElementos-1; i++){
            vetor[i] = 1;
        }
        vetor[i] = 123;

        //----BUSCA PARALELA----
        numThreads = atoi(argv[1]);
        interPorThread = numElementos/numThreads;

        pthread_mutex_init(&mutex, NULL);
        pthread_t *threads = (pthread_t *)malloc(numThreads*sizeof(pthread_t));

        int rc;

        for(i = 0; i < numThreads; i++){
            rc = pthread_create(&threads[i], NULL, min, (void *)i);
            if(rc){
                printf("ERROR: return code from pthread_create() is %d\n", rc);
                exit(1);
            }
        }

        for (i = 0; i < numThreads; i++){
            //join bloqueia a main ate que as threads terminem
            rc = pthread_join(threads[i], NULL);
            if(rc){
                printf("ERROR: return code from pthread_join() is %d\n", rc);
                exit(1);
            }
        }

        max = maiores[0];
        for(i = 0; i < numThreads; i++){
            if(max <= maiores[i])
                max = maiores[i];
        }


        printf("\nMin:   %d\n", max);
    }
    else
        printf("vetor nul\n");

    return 0;
}