DFA.c

#include <stdio.h>
#include <string.h>

int main(void)
{
    int nstate, nalphabet;
    int transition[64][10];
    int start_state;
    int naccept_state, accept_state[64] = {0};

    // read definition
    scanf("%d %d", &nstate, &nalphabet);
    for (int i = 0; i < nstate; ++i) {
        for (int j = 0; j < nalphabet; ++j) {
            scanf("%d", &transition[i][j]);
        }
    }
    scanf("%d", &start_state);
    scanf("%d", &naccept_state);
    for (int i = 0; i < naccept_state; ++i) {
        int n;
        scanf("%d", &n);
        accept_state[n] = 1;
    }

    // skip return
    {
        char buf[256];
        fgets(buf, 255, stdin);
    }

    // test strings
    for (;;) {
        char str[256];
        int len, state;

        // read string
        if (fgets(str, 255, stdin) == NULL)
            break;
        len = strlen(str) - 1;
        str[len] = '\0';

        // run automaton
        state = start_state;
        for (int i = 0; i < len; ++i) {
            char a = str[i] - '0';
            state = transition[state][a];
        }

        // print result
        if (accept_state[state])
            printf("accepted (%s)\n", str);
        else
            printf("rejected (%s)\n", str);
    }

    return 0;
}