#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>

int main(int argc, char *argv[]) {
    if (argc != 4) {
        fprintf(stderr, "Utilizare: %s <fisier> <string-tipar-1> <string-tipar-2>\n", argv[0]);
        exit(-1);
    }

    pid_t pid[3];
    pid[0] = fork();

    int pipe1[2];
    int pipe2[2];
    int pipe3[2];

    if (pipe(pipe1) < 0) {
        fprintf(stderr, "Eroare pipe().\n");
        exit(-1);
    }

    if (pipe(pipe2) < 0) {
        fprintf(stderr, "Eroare pipe().\n");
        exit(-1);
    }

    if (pipe(pipe3) < 0) {
        fprintf(stderr, "Eroare pipe().\n");
        exit(-1);
    }

    if (pid[0] < 0) {
        fprintf(stderr, "Eroare fork() cititor.\n");
        exit(-1);
    }

    if (pid[0] == 0) {
        // cod cititor
        close(pipe1[0]);
        dup2(pipe1[1], 1); // redirectioneaza iesirea standard catre pipe
        close(pipe1[1]);
        close(pipe2[0]);
        close(pipe2[1]);
        close(pipe3[0]);
        close(pipe3[1]);

        execlp("cat", "cat", argv[1], NULL);
        fprintf(stderr, "Eroare execlp().\n");
        exit(-1);
    }

    pid[1] = fork();
    if (pid[1] < 0) {
        fprintf(stderr, "Eroare fork() filtrator-1.\n");
        exit(-1);
    }

    if (pid[1] == 0) {
        // cod filtrator-1
        close(pipe1[1]);
        close(pipe2[0]);
        close(pipe3[0]);
        close(pipe3[1]);
        dup2(pipe1[0], 0);
        dup2(pipe2[1], 1);
        close(pipe1[0]);
        close(pipe2[1]);

        char regex[64];
        int n = sprintf(regex, ".*%s.*", argv[2]);
        regex[n] = '\0';

        execlp("grep", "grep", "-E", regex, NULL);
        fprintf(stderr, "Eroare execlp().\n");
        exit(-1);
    }

    pid[2] = fork();
    if (pid[2] < 0) {
        fprintf(stderr, "Eroare fork() filtrator-2.\n");
        exit(-1);
    }

    if (pid[2] == 0) {
        // cod filtrator-2
        close(pipe1[0]);
        close(pipe1[1]);
        close(pipe2[1]);
        close(pipe3[0]);
        dup2(pipe2[0], 0);
        dup2(pipe3[1], 1);
        close(pipe2[0]);
        close(pipe3[1]);

        char regex[64];
        int n = sprintf(regex, ".*%s.*", argv[3]);
        regex[n] = '\0';

        execlp("grep", "grep", "-E", regex, NULL);
        fprintf(stderr, "Eroare execlp().\n");
        exit(-1);
    }

    // cod parinte

    close(pipe1[0]);
    close(pipe1[1]);
    close(pipe2[0]);
    close(pipe2[1]);
    close(pipe3[1]);

    char buffer[512];
    int r;
    int k = 0;

    while ((r = read(pipe3[0], buffer, sizeof(buffer)))) {
        buffer[r] = '\0';

        for (int i = 0; i < r; i++) {
            if (buffer[i] == '\n') {
                k++;
            }
        }
    }

    close(pipe3[0]);
    fprintf(stdout, "%d\n", k);
    return 0;
}