#include<unistd.h>
#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/wait.h>

#define NUM_THREADS     10
#define BLOCK           200

struct thread_arg{
        char *filename;
        int start;
        int end;
};

int x = 0;

void female_30_50(struct thread_arg *);

int main (int argc, char *argv[]){

        int err_code, i=0, p_id, p[2], counter=0;
        char token[1000];

        struct thread_arg myArg[NUM_THREADS];
        pipe(p);

        while (1) {
                printf("In main: creating thread %d\n", i);
                myArg[i].filename = argv[1];
                myArg[i].start = BLOCK*i+1;
                myArg[i].end = BLOCK*(i+1);
                p_id = fork();

                if (p_id < 0){
                        printf("Cannot create a process.\n");
                        exit(-1);
                }

                if(p_id==0){
                        close(p[0]);
                        dup2(p[1],1);
                        female_30_50(myArg+i);
                        return 0;
                }
                i++;
                if(i>=NUM_THREADS) break;

        }

        close(p[1]); /* close the fd of the rear end of the pipe */
        dup2(p[0],0);

        while(scanf("%s", token) != EOF){
                printf("Parent says %s\n", token); /* add the suffix string */

                fflush(stdout);
        }
        wait(NULL);
        return 0;

}

void female_30_50(struct thread_arg *td){

        long int DATA[4];
        char comment[256];
        int i, n, m, hid, flag;
        n=0;
        int start, end,lines =0;

        FILE *rFile, *wFile;
        rFile=fopen(td->filename, "r");
        wFile=fopen("output.txt", "w");

        start = td->start;
        end = td->end;

        fgets(comment, 256, rFile);

        while(!feof(rFile)){
                lines++;
                fscanf(rFile, "%ld %ld %ld %ld", DATA, DATA+1, DATA+2, DATA+3);
                if(lines >= start && lines <= end){
                        if(DATA[3] == 2 && DATA[2]>=30 && DATA[2]<=50){
                                n++;
                                fprintf(wFile, "%ld", DATA[1]);

                        }
                }
        }

		x = x + n;

        printf("%d\n", n);
        fclose(rFile);
        fclose(wFile);
}